Mark Romero 2

Yeah, the 6K photo mode is actually 5.2K 200Mbit/s H.265. It’s not bad at all but it’s 30fps. As I mainly shoot in 24fps, I like the slight slowing down of the 30fps on a 24fps timeline. I usually don’t need that much resolution but it’s nice it’s there. As for the Long GOP codecs on the S-Series, I’ve read that they’re much more robust than the older Long GOP of the GH cameras. For this reason for example Alex from emotive color always recommended All-I on the GH5 but also Long GOP codecs from the S-Series for his LUTs.

Correct, all the codecs on the S1 / S5 / S1R are Long GOP (unless you hook up a recorder, where you can record in ProRes, ProRes RAW, or BRAW.
Further, the S5 has internal recording time limits has no internal 6K (the S1 does). There is some "cheat" with 6K photo mode but I haven't used it really. I read that it is only 5K, not 6K or something like that.
@interceptor121 Did an examination of the h.264 codec Long GOP frame distributions and came to the conclusion that while the 10-bit codec have more color fidelity and flexibility, the 8-bit codecs offer better distribution of the GOP frames and would be less likely to suffer from motion artefacts.
I don't believe he was able to analyze the h.265 codec though, but he said from his experience it is probably better to use 200Mbps h.265 instead of the 150 / 100Mbps h.264 codecs.
I will admit that I haven't even TRIED shooting in h.265 at all because I thought it would kill my computer. Maybe my RTX 2060 Super has hardware acceleration for it though??? (I don't know how well my i7-6700, which is now three or four generations old, will handle decoding h.265).
I guess there is always transcoding, right???
 

I have been using the S5 human detect continuous AF quite a lot recently. I shoot using the CineD2 profile (standard kit lens) and mainly outdoors, hand held. It works pretty well and am a bit baffled by the criticism it gets here. Maybe that is because people expect 99% success with it when in reality it is more like, I dunno 85%? I suppose with crucial commercial shoots this becomes an issue. But, with practice you get to know when it falls over - mainly too dark or too bright and movement is too rapid (so practice with it really does help like most things). Avoid that and it works the vast majority of the time very well and I love the look it gives. In fact as I have got experience with the S5 generally, I have grown to love it more and more, faults and all.

Thanks for the food for thought.
The one saving grace for me is that none of the m43 wide zooms have lens stabilization, and they all rely on IBIS instead.
For me, that will be difficult because even though I shoot my real estate videos on a gimbal, I basically NEED only TWO-axis IBIS, along with the three axis that are controlled with lens stabilization.
Otherwise, when shooting equivalent full frame of 16- 30mm (i.e., 8-15mm on m43) you get a lot of corner warping if only using IBIS.
At least as far as I have experienced so far. Maybe the GH6 will somehow rectify the corner warping problem???

Some thoughts.....
Think of the total ecosystem that you have
This includes cameras, lenses, batteries and chargers, and all your accessories, and then build a system that works for you.  Think about failures and having equipment redundancy too.
My travel setup is two MFT cameras and an action camera.  If I want to shoot simultaneously then I can use the same lenses across the two bodies.  If my action camera dies I can use a wide on a second body to emulate it.  If my main camera (GH5) and lens (Voigt 17.5mm) and mic (Rode VMP) disappear then I have backups for those three (GX85, 14mm f2.5, Rode Video Micro) which are small and I can easily carry as a spare.  If my backup / 2nd setup dies then I can use my action camera in a pinch and there's also my phone.
The difference in DoF is 2 between MFT and FF, so to match the FOV and DoF of a 50mm at F4 on a FF camera, you would need a 25mm F2 lens for an MFT camera.  But you should also think about the base ISO of 2000 on the GH6 as I'd assume you'd be using V-Log and DR Boost, which might require new NDs to suit the new lenses you'll probably have to buy.  
Don't just think of the fact that MFT has faster lenses with the same DoF, because the sensor is smaller and therefore has higher noise and therefore requires more light to get the same performance, but then technology of the sensor and processing all apply and then there's the sensors with dual-ISO or dual-gain and then there's blah blah blah blah.  Long story short - there are too many variables that factor in to be able to predict low-light capability.
The only real way to compare low-light is to look at a test of the two cameras you're comparing shooting the same scene with equivalent lenses.

Thank you again, @kye, for once more making my life a living Hell...
😀
In all seriousness, I am thinking about getting a GH6 to replace my S1.
The better autofocus, lighter weight, bigger lens selection, ProRes 4:2:2 internal, ability to record to an SSD, all-i codecs, appeals to me, and at 4K 60fps (using the dynamic range boost) of the GH6, the DR is going to be roughly equivalent since I tend to be one of those people more likely to stop down a lens, and the added DOF of m43 would allow me to use faster lenses for the same DOF (so use one-stop lower aperture???) Math is not one on of my skills.
My only two real issue after that is mixing and matching lenses with my full frame S5, and the fact that the S5 has a thirty-minute time limit (and no internal 6K). 
I guess logically I would sell the S5, keep the S1 and add the GH6. But logic and I aren't really on speaking terms 🙈
 

Thank you again, @kye, for once more making my life a living Hell...
😀
In all seriousness, I am thinking about getting a GH6 to replace my S1.
The better autofocus, lighter weight, bigger lens selection, ProRes 4:2:2 internal, ability to record to an SSD, all-i codecs, appeals to me, and at 4K 60fps (using the dynamic range boost) of the GH6, the DR is going to be roughly equivalent since I tend to be one of those people more likely to stop down a lens, and the added DOF of m43 would allow me to use faster lenses for the same DOF (so use one-stop lower aperture???) Math is not one on of my skills.
My only two real issue after that is mixing and matching lenses with my full frame S5, and the fact that the S5 has a thirty-minute time limit (and no internal 6K). 
I guess logically I would sell the S5, keep the S1 and add the GH6. But logic and I aren't really on speaking terms 🙈
 

They might pay Adobe and let the GH6 use CinemaDNG.

Imma buy this as soon as I can lol.

If it had internal prores RAW that would be icing on the cake, but we can thank RED for that not happening.

Even with the M1 chip mac H264 and H265 still suck for editing. Its a huge hassle to transcode to Prores. It makes me not want to shoot on the S1. External recorders are annoying as well.
 
There is a question of why not just get a Pocket 4k but I think the GH6 has many advantages including an inherently better DGO sensor. Of course you don't get BRAW, but I really don't need RAW. I am also a loyal Panasonic guy.

I think the GH6 is a triumph of incremental upgrades that provide a real difference when shooting run-n-gun video in the real world.
With the headline features so prominent, it's easy to miss the many smaller improvements that can actually make a big difference to shooting.
We talk about cameras like they're museum pieces or engineering spectacles, but often these things don't translate to the real world.  The following are my views of the GH6 from the perspective of a travel videographer upgrading from the GH5.  I've tried to include as many example images as I can - please note that these aren't fully graded and are often compromised due to me pushing the limits of what is possible from the GH5, what was possible under the circumstances, and what my limited skills could create...
But let's get some obvious things out of the way first.
Things I don't care about.....
Autofocus
The AF is improved.  People who used the GH5 AF will like the GH6 AF, and people who didn't like the GH5 AF probably won't be moved by the GH6 AF.  I don't use it, basically ever, so I don't care.  If you do care, then good for you..  move along, nothing to see here.
Extra resolution
There's more resolution, but the GH5 had enough resolution for downsampled DCI4K and lower resolutions, and the 2x digital zoom and ETC modes provided useful cropping modes as well.  The extra resolution doesn't really matter to me.
Size and weight
I care about this a lot actually, but it's not substantially larger than the GH5 from the front, which is the dimension that matters when filming in public.  The extra depth is immaterial when you have a lens on the camera.  The extra weight is unfortunate, but isn't that much and is well worth it for the fan and screen improvements.
Internal Prores
Prores is a professional codec that offers considerable improvements throughout the whole workflow.  I'm not going to say much else on this as I created another thread to talk about this but it's great to have the option, and I definitely appreciate it.  Many people were happy with the GH5s codecs, especially the 10-bit 422 ALL-I codecs, which were a shining beacon in a sea of poor-quality IPB cameras, but even those have been improved....
Huge improvements on h264/h265 codecs
The GH5 had 200Mbps 1080p and 400Mbps DCI4K, but the slow-motion modes are limited to 150Mbps (4K60) 200Mbps (1080p60) or 100Mbps (1080pVFR up to 180fps) and the effective bitrate dropped significantly when you conform your 60p or 180p footage to 24p - as low as 13Mbps!!.  The GH6 has 4K60 at up to 600Mbps (SD card) or 800Mbps (CFexpress type B) - an effective bitrate of 320Mbps, and in 1080p240 800Mbps which is an effective bitrate of 80Mbps.  
Oh, and these are all 10-bit 422 ALL-I, as opposed to the GH5 8-bit 420 IPB.
Oh, and also also, the 120p is now in 4K too.
If you're shooting sports this is a big deal as often players are in direct sunlight, depending on the time of day there might not be much ambient fill light, and any reflections from the field may be strange colours such as green grass, or various coloured artificial turf, which will drastically benefit from the 422 10-bit when colour correcting footage.  The extra bitrate is also great for having clean images when players may be bright against a very dark background really highlighting any compression nasties on their edges.  The ALL-I will be great in post too.
I'm curious to see what the 300fps looks like in real-world situations, but I've shot a lot of sports with 120p and it seems slow enough to me.
Dynamic Range Boost
This is a big deal for anyone recording in uncontrolled conditions, and especially for travel.  This isn't a vanity exercise or BS tech nerdery, this is a real creative consideration.  When you're shooting travel, the film is about the location and the experience of the people in that location, and the weather is a key consideration of this.  With the GH5 I often had to choose between clipping the highlights (ie, sky) and exposing for the people.  I also chose to expose for the sky on my XC10 and in combination with 8-bit C-Log recorded a large amount of spectacularly-awful looking footage of my honeymoon.
Here's a frame of C-Log SOOC from that debacle:

The shot was also mixed lighting with the subject in the shade, being lit by a coloured Italian shop-front immediately behind me that was in full sun....

Being forced to decide between the subject and the sky is problematic if the shot you want is "person at location X at sunset" and you can't feature that person and also the sunset.
It's also relevant for anywhere with tall buildings that create deep shade - the below is a nice dynamic image but it's a tad overdone and not how we actually see the world:

My experience with shooting the OG BMPCC / BMMCC is that their ~2 stop advantage in DR over the GH5 almost completely covers this gap.  Images with someone standing in-front of a sunset no longer feature either an anonymous shadow person swimming in technicolour-grain or a digitally clipped sky.
The GH6 DR Boost feature will help in these situations, allowing subjects to be filmed in-context rather than only in select locations were the light is just right but the scene is irrelevant.
Would more be better?  Sure.  I can hear lots of people thinking "go full frame then - moron" but the GH5 was (until now) a camera with a unique set of features not bettered by any other offering for this type of travel shooting, so while the current alternatives give with one hand they also take away with the other, normally taking away a lot more than they give.
Full V-Log
Having a colour profile that is supported natively by Resolve is a huge thing for me, as it allows WB and exposure adjustments to be done in post without screwing up the colours.  This is important because in shooting travel there are times when you can't even stop walking to get a shot, let alone have enough time to pause, get exposure dialled in, and heaven-forbid to pull out a grey-card and do a custom WB!  A great man once said "tell him he's dreamin"!
This lighting all looked neutral to the naked eye - GH5 HLG SOOC:

The advice I got from the colourists on that was to lean into it and just pick one or the other and balance to those, but sometimes the mixed lighting isn't really something you want to lean into....  GH5 HLG SOOC - look at the colour temperatures on the grey sleeve from what appears to be the strip-light from hell hanging just above their heads:

Better Low-light performance
Filming in available light in uncontrolled conditions often means needing to use high ISO settings.
This is a shot I've posted many times before, and the BTS of me shooting it, in a row-boat lit only by the floodlights on the river bank maybe 50m away.  

Notice that the smartphone taking the BTS photo couldn't even focus due to the low-lighting.

It was using the GH5 in full-auto (likely a 360-degree shutter) and with the Voigtlander wide open at F0.95.  I don't know what the ISO on the shot would have been, but there's quite a bit of noise, especially considering this is a UHD clip downsampled from 5K in-camera (200% zoom on a UHD timeline):

I don't mind the quality of the noise actually, and it responds to sharpening really well giving quite an analogue image feel, but if the image is this noisy then the colours aren't going to be at their best, and that isn't desirable.
There are a number of fast primes on MFT (ie, faster than F2) but getting sharp images wide-open is problematic, even from the very-expensive Voigtlander f0.95 primes.
The GH6's improved low-light is great, and not only does it allow recording in ever-darker environments, but it also allows the use of modest lenses and faster lenses stopped down to be within a higher quality part of their aperture range.  An extra $1000 cost on the body of a camera seems like a lot, but if it saves you $500 on every lens because you can buy slower lenses then it's an investment that has a reasonable return.
...and lest you think that the above is an extreme example, having good low-light performance is really just about filming people doing what they're doing, and in case somehow you haven't noticed, it's dark outside about half the time and people go out into it and do things.
Another example, here's a shot taken right at the end of blue-hour:

and minutes later, here's a shot showing what you can get when lit only by the light of a phone, and providing a reference for how dark this location was:

Think of the benefits of better low-light performance here.... it's very low-light, mixed colour temperature lighting, and the main feature is skintones.  The noise on the GH5, with the Voigtlander wide open is pretty brutal:

New Screen
My XC10 has amongst the nicest ergonomics of any camera and a big part of that for me was the tilt screen that didn't get in the way when using your right hand to hold the camera and the left to support the camera and manually focus the lens.  The fact that the new GH6 screen allows for both tilting as well as for flipping is great.
Contrary to what many believe, the 'flippy' screen is actually very useful for filming things other than yourself.  Any time when you cannot stand directly behind the camera is when the flipping screen is useful.  I have used it while filming out of windows (such as in moving vehicles, filming the view around the corner of a panorama framed by an arch, or taking a sneaky shot of the kids around a corner without them spotting me and pulling faces).  
Sometimes you need to hold the camera in funny ways to get a shot:

They're also very useful for those who want to take vertical photos from a low or high angle.
Fan
The GH5 never overheated on me, even in desert conditions, unlike my iPhones have on many occasions, and the GH6 will never overheat either.  It's not an "improvement" in the sense that it doesn't offer anything new, but it is a guarantee that all the extra other features won't come at an unacceptable cost.  Having a camera that overheats is just stupid, and Panasonic doesn't insult us by providing tools that aren't reliable.
Punch-in while recording
Checking focus while recording is a pretty fundamental thing, and the GH5 didn't have it (and didn't have the best focus peaking either) but now the GH6 does.  Boom.
Custom Frame Guides
The frame guides on the GH5 were worthless - pale dotted lines that were difficult to see under ideal conditions, let alone while holding the camera at arms length in a moving vehicle. The GH6 has custom frame guides that have a much more visible outline and also dim the out-of-area image, making it super easy and intuitive to use.
Frame from @Tito Ferradans review on YouTube:
 

I might be tempted to engage this for a 2.35:1 permanently and then choose what ratio to use in-post when I get to editing.  I've tried to shoot for this ratio before with the GH5, forgot and couldn't see the frame guides and intuitively composed like normal, and then downloaded the footage and found that I'd framed every shot too close for the ratio.  Fail. 
Buttons and controls
The GH6 has more programmable buttons than the GH5 (which was already great), and the extra custom slot C4 on the mode dial is very welcome.  I have my GH5 configured to be C1 1080p24, C2 1080p60, C3-1 1080p120, C3-2 4K24 (in case there's something I'd need 24p for), and C3-3 as 4K manual everything for shooting camera tests.  The first four modes are ones I want to just be one dial away while I'm out shooting, so having the extra one is really useful.
The GH5 also saved the preset focal lengths for the IBIS on a per-profile basis, so when you switch profiles you switch focal lengths.  This is important because when the camera goes to sleep it wakes up but forgets the focal length and goes back to the default one for that profile.  As such, you could duplicate profiles and use them to swap between focal lengths, like if you were recording sports on a manual zoom lens, just to name a purely-theoretical example that no-one would ever contemplate....

Better IBIS
The GH5 IBIS is great, and when you shoot with fully manual primes and without a rig, is an important function.  Having improved IBIS on the GH6 is very welcome and can really help salvage shots that wouldn't otherwise have made the cut.  One of the killer features of action cameras is that you can put them anywhere and get a huge variety of images while out in the real world, and that works for MILCs too, but if you're balancing on a chair and shooting at full arms-reach to get a shot and the IBIS isn't able to take up the slack and stabilise it, then it won't make the edit.
It doesn't matter how good the stabilisation of something is, there are instances where it will fail, and I seem to keep finding them.
USB-C port
The Prores and high bitrates will chew through storage and the ability directly record to an SSD would be spectacular.  Being able to charge the camera with USB-C would also be useful in some instances. 
In camera LUT support
I'm yet to see how this is implemented but LUTs can be great references while shooting.  You can use LUTs for things like false-colour, sure, but I'll be very interested in experimenting with ones that are very high contrast to allow for better visibility in bright conditions, and other more extreme applications that help you get the shot.
I normally use the EVF on the GH5 as it eliminates ambient light and adds another point of contact for better stabilisation, but sometimes you have to use the screen and it's not always ideal, so these could be useful for that.
Better colour science?
The GH5 colour science wasn't winning any awards, and the GH6 combination of V-Log + Prores + higher bitrates + higher DR seems to be noticeably better, which is a welcome improvement for me, especially as I am struggling to shoot in difficult situations often involving mixed WB lighting and other nasties.
The latitude tests from CineD look spectacular:



This will allow huge flexibility for imperfect shooting conditions.  Many times I pull up the shadows in an image (maybe I was trying to get the subject and the sky in the shot - shock horror) only to find the shadows a tinted awful mess.  If they look like the above then it will be tremendously useful in practice.
4-channel audio recording with the XLR module
This is slightly tempting for me.
In post I want a stereo ambient sound, and I also want a directional audio from a shotgun mic, ideally with a safety-track.  I can get either of those with the GH5 pretty easily by using the Rode Videomic Pro Plus with the safety-track feature enabled, and simply unplug it when I want a stereo ambience track using the cameras internal microphones (which are good enough if you're only using this in combination with music and other sound-design).
But the problem is that I don't know when something will happen, so if I'm recording stereo ambient sound I don't know if my subject will say something at the same time that a car goes past behind me, and I also don't know if my subject will say nothing while I'm recording directional mono audio and then before I know it we'll be somewhere else and I'll have no ambient audio from that location.  If this situation seems far-fetched, you've obviously never been on a tour bus in a third-world country before, where you might get dropped off near a small market, you then walk though the market with your group, where there is a stall every 5 steps with a different composition / lighting / and ambient sounds, and there is literally only room for people to walk single-file and you don't have time to stop at each interesting booth for a minute as you capture different compositions and audio options without losing your tour guide.  
Being able to stop for a few seconds, smile at the person there, and grab a few seconds of action with directional audio and ambient sounds would be really useful.
 

I don't fancy the added size of the module though.  
Audio screen
The GH6 has an audio button function that brings up an audio screen showing all the audio things you'd want.  Perfect for quickly checking how the audio is going.  With so much going on while shooting it's easy to forget to look at the meters OSD, and having everything in one place seems excellent.
I've screwed up the audio on many occasions, so this will be quite useful.
In summary....
The GH6 has tonnes of little improvements that I think will make it a much more useful camera when out in the field recording things in difficult conditions as they happen.  It looks like Panasonic has done a great job in not just grabbing headlines, but in actually taking the things that niggle or limit real shooters and making them better.
Now, if only the world would return to a state where I'd feel remotely comfortable wandering out into it with a camera in hand.....

I agree, it is a new camera, and probably will see an S1H replacement soon(ish).
On the other hand, I can always dream, right?
Just saying that if they somehow put PDAF and allowed recording out to an SSD via USB, well, I think you might see a lot of youtubers with videos titles like, "I'm leaving CaNikSony for Panasonic."

The S5 is still a relatively new camera, I don't think a replacement comes in the near future. My prediction is: a replacement for the S1H will come first, maybe next year? And after that we could see an S5 replacement, maybe in 2024 or so. I don't think there will be a replacement for the S1 though...

I think this is what most people are going to do.  It troubles me though because you are shooting through 3 bits of tinted glass (2 polarised planes in the variable ND).

My experience of variable ND (Tiffen 2 - 8 stops) is mixed.  Around 85% of the time it is fantastic with little to no noticeable cast.  Many shots I forget that there was even any ND used.

But the times when problems are introduced can be very hard to predict.  Weird casts seem to appear based on such criteria as window coatings in buildings (especially office blocks and new-build public buildings), light bouncing off buildings, the sun at certain angles to the filter, etc.   The cast can also range from muddy brown to grey-blue (at high ND's).

It can also play funny with other filtration, such as diffusion.  All of which makes me a little nervous about stacking variable ND with more stuff. 

I was really happy when I realised that the GH5 2x in 1080p was downsampled - it is even downsampled in the 1080p60 too, so if you shoot 1080p ALL-I codec then you get full-readout and 2x digital zoom downsampled in every framerate, and you also get the 1:1 ETC which is a ~2.5x zoom.
How odd that the larger cameras don't have as good video modes in this way.  The GH5 was the flagship though so maybe the S1H has those modes?
Fascinating about the 16-bit output.  I guess it might depend on the sensor mode.  IIRC other sensors sometimes have a higher bit-depth readout mode with limited fps, and then a reduced bit-depth mode where they get higher fps readouts, so maybe the 16-bit can only happen at 10fps or something.  
It would be great to see if that's possible at the 60fps speeds that the DR boost feature can do for video.
That makes sense.  Potentially then it's quite a different equation for your ND setup, but I keep thinking that all you need to do is work out what the maximum and minimum amount of ND you will need in daylight and just buy a fixed ND that compliments your vND to give you that range.  Then after sunset you remove the fixed ND and your vND should cover the range of shooting under artificial lights.  ISO 2000 should be a good base ISO for most low-light situations, so you should be using your vND even after dark anyway.
The GH6 is 5760 x 4320 and the GH5 is 5184 x 3456 so if you multiply those out then you get a 38% increase in total number of pixels, or a 11% increase in width, so not entirely sure where they're getting that number either.
Still, it's more pixels, and not stupidly more pixels, which is probably the right balance.
Yeah, odd, but I agree that the GH6 is a winner.
I see so many tiny little improvements they've made - I was contemplating writing a summary of what improvements I see that would be relevant to me in the real world and how I shoot.
The ISO performance on the GH6 is pretty darn good!

It's all about the quality of the isolation.  it can be tough to get, say, a clean skintone isolation even with a really strong codec at times.  If the colour data is thin you either end up with areas of skin that just won't key, or parts of the background that just wont separate.  I've had to just abandon secondaries at times.

Totally agree about Canon.  They seem to have some compression fairy dust.  The C200 8-bit was remarkable.

I think what people miss out here is secondary grading isolation, which also benefits from a rich data environment. 

I don't consider this specialised at all.  Its a part of a well-rounded grading workflow.  I don't end up using it for every single project, but if anybody is not using secondaries at all, well... they probably should be in my opinion.

Just what I DIDN'T need to hear: another reason to buy a GH6 😬
Hopefully, Panasonic NEVER makes the continuous AF reliable 🤞

Yes, that was the one.
I don't think I would notice ANY difference between the all-i internal codecs and prores external unless I was keying, which i freaking HATE to do (I mean, I hate even trying to light a green screen so you can imagine what I am like at 4:00am trying to key around hair, but then again, I am using the 150Mbps 10-bit 4:2:2 Long GOP from the S1 or S5).

Yes, that was the one.
I don't think I would notice ANY difference between the all-i internal codecs and prores external unless I was keying, which i freaking HATE to do (I mean, I hate even trying to light a green screen so you can imagine what I am like at 4:00am trying to key around hair, but then again, I am using the 150Mbps 10-bit 4:2:2 Long GOP from the S1 or S5).

True. 
I have been thinking about selling all my Sony aps-c gear and my Panasonic S1 and getting the GH6 (and use my S5 on a gimbal for real estate because I am often shooting at ISO 4,000). I have an Oly E-M1 MK II for fun, so it would be nice to have lenses that could work well on the GH6 and the E-M1 MK II.
The DR of the GH6 in DR Boost mode is going to be more or less the same as the S5 / S1 when shooting 4K 60p (since it shoots it in a crop at 4K 60p)
Just the thought of shooting at ISO 2,000 and all the ND filters is kind of an annoyance. 
Wishing they had internal NDs

I'm not sure what it is on the GH5. On the S1 / S5, V-LOG native ISO is 640.
But your point is well made. It is technically only a stop and 1/3rd (or 2/3rds) more.
Normally I shoot with a three-stop ND filter on the S5 during the daytime, but I am usually shooting at around f/8 to f/11. So I think mostly for my shooting I would end up around f/4 on m43. 
So maybe around five or six stops of ND would be what I am used to.

I don't have any experience with those power zoom lenses, but one feature that I think would be of huge benefit from them is the ability to hold down the zoom rocker just a bit and do a smooth zoom during a shot.
The more serious MFT lenses are nice, but I'm not sure that the manual zoom ring is damped and smooth enough to really pull off a flawless zoom during a shot, certainly my second-hand 12-35mm and kit 14-42mm zooms aren't.
That was a thing that those ENG lenses were really good at weren't they?
Definitely agree there.
In terms of firmware updates, do we even know when the camera will be shipping?  I haven't seen anything about it so am curious.  No point having firmware updates if no-one has the camera!!
I'll be curious to see what the math is like for shooting at, say, f0.95 in bright sun, at ISO2000 for high DR mode, and what that equates to in an exposure time.
I did note that they improved the shortest shutter time of the camera, so maybe that is why.  Not much good having a camera that can't expose properly in aperture priority mode while wide open at noon - that would be seriously embarrassing I'd imagine!
In terms of ISO2000 compared to 800 (wasn't 800 the native ISO for Vlog on the GH5?) isn't it only slightly more than a stop more exposed?  If so, you only need to add a single-stop of ND to your setup and it's the same.  Or am I missing something?

I saw a video a while back comparing the all-i codecs on the GH5 with prores recorded on a Ninja and it seemed like the prores was better at avoiding macroblocking in motion. So I guess in theory it allows better keying in post. I thought the video was by Andy Dax, but apparently it was by another group of filmmakers (in Norway)? I can't seem to find it on the Andy Dax channel.

Good point.
Also, good on Panasonic for allowing the ability to punch in while recording. Really wish my S1 and S5 had that ability.

I will be the first to admit that it does seem to be just about everything other than really reliable AF everything a person really needs. With all the super-fast cheaper lenses out now even the DOF low light thing is off the table.
I still wish they would set in stone what and when the firmware updates are coming. They did a good job on it no doubt, but I think they had to do it to be honest. If you can't shoot decent video with this camera you need to give it up.