Chamsom

Panasonic (or at least their partner: Sigma) need to play this same game. 
Bring out an absurdly cheap couple of lenses. 
Don't care what they are, just make them cheap and preferably more than one. 
Could be a 40mm f4 pancake for $199. 
Could be a 35mm to 105mm variable f-stop zoom for $250
Could be a 50mm f2 for $199
Could be a 35mm f2.8 for $299
Whatever, just make a couple of them asap! To draw people into their L Mount ecosystem.
As they have to play the same game the other companies are playing. Nikon/Canon/Sony/Fujifilm/Pentax all do this. (yes, even Pentax!)
Pentax 50mm f1.8 = $97
Pentax 35mm f/2.4 = $117
Canon EF 50mm f/1.8 = $125
Canon EF-S 24mm f/2.8 STM Lens = $129
Nikon 50mm f/1.8D = $132
Nikon DX 35mm f/1.8G = $180
Pentax 40mm f/2.8 (it's an amazing pancake lens!!!) = $230
Nikon DX Macro Lens 40mm f/2.8G = $280
Nikon 28mm f/2.8D = $287
Canon RF 50mm f/1.8 = $149 
Canon EF-M 22mm f/2 = $179
Fujifilm 35mm f/2 = $199
Sony FE 50mm f/1.8 = $248
Sony E 16mm f/2.8 (pancake!) = $248
Canon RF 16mm f/2.8 = $249
Nikon Z 40mm f/2 = $277
Nikon Z 28mm f/2.8 = $277
They need to do the same too for camera bodies, how else can they compete with the gateway drugs of: Nikon Z5, Canon EOS RP, Sony a7C / a7mk3 ?? Let alone the other gateway drugs they all have of APS-C cameras for dirt dirt cheap: Nikon Z30, Canon R10, Sony a6x00
Because as fantastically great as Panasonic MFT cameras are, they're unfortunately not a smooth pathway into the L Mount Ecosystem. 
Am glad to hear that Panasonic will keep around the S5mk1, as that's a smart move. 
Because as I'll say over and over again, Panasonic (and Sigma & Lecia) **NEED** a gateway drug (camera) into the L Mount system.
Sony does this by keeping around their older a7mk3 (and even a7mk2!!) at cheaper prices.
If Panasonic had the S5mk1 available for US$1.7K , then dropping down in the second half of this year to US$1.5K, then the S5 would do well at serving that critical niche point. (and just keep on dropping it down by another $100 each year, until five years from now it's being sold for US$1.1K brand new)

The body shape is just... disgusting (and that’s coming from someone who owns and uses a P4K). They should just make the screen AND EVF each a $500 extra, and reshape the body into something more like RED/Kinefinity/ZCam/BGH1.

Here is what’s best I’ve found from over the years...
Option 1  Shoot with a camera that has internal ND feature.
Option 2  Instal fixed ND’s upfront in a rail mounted mattebox - or VND/ circular ND using a filter tray adapter.
Option 3  Rear mounting a fixed or VND (between Anamorphic rear and taking lens front) can work perfectly well, providing the setup is on rails. In bright conditions a collapsed rubber lens hood can also be used to create a lightproof donut that is compact enough to not introduce added vignette. Flares are not affected or dulled...at most an added faint green line is added to the streak flare from the ND’s multi-coating.
Option 3  If rail mounted setup is not used - front mounting ND’s can be attached to front of scope lens by using clamp adapter, or screwing into native thread if using iscorama lens types. If using clamp adapter, some added vignette might be introduced if using wider taking lenses. Fixed value ND’s are usually best used in this scenario since they are usually thinner. VND’s can sometimes introduce issues if used on the front clamp of scope lenses that rotate whilst focusing, since a shifting polarising effect can be introduced. Sometimes front mounting ND filters can introduce added flare effects, usually an added faint green streak line flare is apparent when exposed to intense direct light source.
 
Always best to get the best possible quality filter budget will allow - especially if mounted to front of a rotating scope, since some lower quality ND filters can introduce unwanted texture to bokeh. When these are rotated it can be very distracting to see this artifacts in bright light as well as ugly colour shift. A very decent budget solution is the Hoya PROND64 (six stop fixed ND) - quite capable in bright daylight and easy to rear mount in a rail setup as described previously.
 

Here you go, 
My smallest yet.
Canon 50D + Voigtlander 50/2.8 (DKL mount) + YashicaScope + Aivascope Focuser 8 ( + lots of adapters from china + rapido to have the yashicascope held properly)

watching ebay i'd have to say a $2000 iscorama is rarer than a unicorn ? maybe a year or two years ago possibly ?
Barrel distortion, uneven waterfall bokeh, internal reflections, raimbow artifacts, blooming that is the anamorphic look everyone has been trying to mimic over the years. thats just like trippin without the mushrooms  ?
if you want hype, go visit the p4k thread, more than a million views and that was before the camera was even released ? what we have been doing is having a gentlemen's discussion on a new lens, thats the cheapest by far, that will alleviate most of the issues of buying a anamorphic projection lens and rigging it to work single focus style, that is groundbreaking gentlemen. Pretty sure tito's already said its not perfect. Does it have to be perfect ? no it does not. It just has to give us flares and an anamorphic aspect ratio 1.33 will do for starters

There's quite a few ways to go lightweight, but you didn't mention what sensor size you are going for The Aivascope that @heart0less linked you to is an awesome, single-focus 1.5x for fullframe.  It does not need a focusser, but imho it does need support, because it is rather heavy on the taking lens at around 700 gramms. But Aivascope also makes a smaller scope, for smaller sensors.
Here's mine for instance : GH5 > speedbooster > Nikon 50mm 1.8 pancake > Aivascope 1.75x v2 > ProtoDNA. Quite lightweight, does without rails. (see attached picture)
This gives me perfect 2.40:1 when desqueezing opengate 4:3.
Then again when you go vintage scopes there is quite a lot of choice :
Baby Hypergonar (the 1.75x aivascope is a modern take on that one Yashica Scope (a cute small 1.5x one, which i would double focus) Bolex 8/19 (1.5x bolex flare goodness, one of my favorite baby scopes) Baby Kowa (2x, even more elusive than the Bolex) So you can go for light and small scopes, especially if you stick to m43 or s35 sensor sizes ... but it might take a year or 2 to hunt some baby scopes down... and you better have deep pockets.

Nah, unfortunately it's still too heavy.
I wouldn't feel comfortable / safe to use it without rails.
 
The lightest way to go is Aivascope paired with Focuser-8, but you'd only get a 1.5x strech with it.
 
Looks like this (not my photos):

The Sony A6300 to me is a cinema camera on the go. Super 35mm sensor, wide dynamic range, EVF and a bunch of other little details that you can just use anywhere. I still feel spoiled even though it's relatively "low end" nowadays.

Mine has to be the Sony A7s.    I have had a LOT of cameras this last decade (and a lot including old point and shoot cameras just this year).    I am now on my second A7s (my first broke after years of solid daily use but I was recently given a new one by my family).      After being without one for a year or so, I appreciate being able to put pretty much any lens on it and simply walk out the door and shoot it at any time of the day or night.
I do not need a huge pixel count or tracking AF but being able to put the ISO on auto (currently max 25600) and not worry is wonderful...with almost every other digital camera I have had (A7, GX7, 7D, Nex3N. several Pentaxes a  couple of Olympus digital ILCs, a Nikon and more as well as many P&S, i HAVE had to worry about the max ISO (A7 was almost worry free for me) and in some cases, simply not shoot at night without flash (or light for video).
It isn't JUST having decent high ISO, it is the dynamic range that goes with it too.    The A7s is stilly pretty good for DR at base (still equal or better to ANY M43 and most APSC and many other FF cameras but it does not drop away anywhere ear as steeply as other cameras (I have some cameras that are about the same at their base as the A7s is at ISO 12800).
I am also finding that simple things like the horizon level in the EVF (that does pitch as well) is a godsend for walking around.
Sure the camera has many flaws but the things it does, it does very well.
Your choice?