Duplex

I suggest you start shooting your subject and then decide what extra lenses you need (I bet they will be wide angles - you will need at least some establishing shots). For interiors / architecture 25mm or 50mm lenses etc are only really going to be good for details. And I wouldn't get too hung up on moving from f 1.8 to f 1.4. that's only 2/3 of a stop difference and you'll only be able to take advantage of that if you don't need depth of field. If I had just one lens for MFT it would be the Tokina 11-16 + a Metabones Speedbooster.  

Replace your canon fd 50 1.8 with a 1.4 version. Or for not that much more money you can buy a FL 55mm 1.2. (There's a really good review here http://www.vintagelensesforvideo.com/canon-fl-55mm/) I'd also recommend getting the FD 24mm f2, but that lens will cost you $2-300. There's is a vivitar version in the fd mount that is $100 cheaper which I'd recommend looking into. I haven't used that lens so I can't speak to its performance so please research before you buy. 
There's also, I think, a vivitar 28mm f1.8 which might also be worth looking into.  

Just be aware that this lens, whilst quite sharp, is actually more like an f2.8 lens in light gathering and DOF.

Best is a mater of taste. 
Check the work from some photographers to get inspiration, people like Alexey Titarenko, Rut Blees Luxemburg and Fan Ho to name a few.
 
 

Much more successful than without light! 
Play with it, it's a creative process.  Reflectors and/or LEDs (with or without gels) will make it look good.
 

Test everything beforehand. Fully exposed high ISOs are not as much of a problem as underexposed lower ones.

I think the YoungNuo LEDs are cheap but decent lights:
https://www.amazon.com/YONGNUO-YN600L-wireless-Remote-Control/dp/B00ZFDTM7Y/ref=sr_1_3?ie=UTF8&qid=1480955522&sr=8-3&keywords=yongnuo+led
https://www.amazon.com/YONGNUO-YN360-Adjustable-Temperature-3200K-5500K/dp/B01D2X4A8Y/ref=sr_1_10?ie=UTF8&qid=1480955464&sr=8-10&keywords=yongnuo
 

Those are fine, LED technology has improved a lot with respect to CRI values. 
You need lights (or reflections of light) to have good results, even a million dollar camera looks bad with bad lighting.
 

Just buy a reflector for £10 ( or make one) and use small LED torches that have an option to change beam behaviour. These are a cheap way of learning how to create moods and set up lighting without breaking the bank.

Buy (or rent) some nice LED lights or use some reflectors if you have natural light coming through windows and doors and you should be fine!
 

This is right on the money.
 
For me, I could have spent more getting a somewhat higher end cam, but being on a budget ( and being purely a hobbyist)  I would rather have a mid range camera with a few different lenses, than one high end camera and only a kit lens. Although the 12-23 is actually a great wee performer!
 
It's very easy to get caught up in the gear side of things. I spent way too much money and time on cameras for still photography over the last few years, thinking that better kit equals better photos and while obviously it's a contributing factor in certain areas, it really comes down to the skill of the user in 90% of situations.
 
Now that I'm more focused on trying to learn video, I'm determined to do it to a budget because as I mentioned it's purely a hobby. M4/3 often gets slated, certainly in the photographic world as there is a huge amount of gear snobbery, but I actually don't mind because there's nothing more satisfying than showing a great picture and then explaining that I didn't need a huge full frame DSLR and £1000 lens to take it!

This is right on the money.
 
For me, I could have spent more getting a somewhat higher end cam, but being on a budget ( and being purely a hobbyist)  I would rather have a mid range camera with a few different lenses, than one high end camera and only a kit lens. Although the 12-23 is actually a great wee performer!
 
It's very easy to get caught up in the gear side of things. I spent way too much money and time on cameras for still photography over the last few years, thinking that better kit equals better photos and while obviously it's a contributing factor in certain areas, it really comes down to the skill of the user in 90% of situations.
 
Now that I'm more focused on trying to learn video, I'm determined to do it to a budget because as I mentioned it's purely a hobby. M4/3 often gets slated, certainly in the photographic world as there is a huge amount of gear snobbery, but I actually don't mind because there's nothing more satisfying than showing a great picture and then explaining that I didn't need a huge full frame DSLR and £1000 lens to take it!

I was using the transitions wrong, I didn't realise that you needed to overlap the clips for them. I've found out now how to use them, and also to use the simpler fades, and everything's running fine now.

The GX85 seems like the best value on the market if you're a shooter desiring 5-axis stabilization.  It's a cheap cam with good IQ and the 5-axis works quite well.
Who can argue with that?
Would I say it's a great camera overall?  No.  But it's an AWESOME camera if you're buying it to do what it's strengths allow you to do --'kuz you get more for less.

4k export is enabled for the free version of resolve.
What's not included is 3d stuff, noise removal and lens distortion fix.

Wow! Quite a package for free. Of course maybe a different workflow but worth considering!

Oh wow, that is new, they didn't have that in the free version before?? When did that come into it?
Though I see it is not 4K DCI, the free version has a limit of UHD.
 
https://www.blackmagicdesign.com/products/davinciresolve/compare

Its been a couple of years now
I think since 2013. Always felth it was sufficient for my needs and I could crop it to "look"like dci.

+1 for black magic resolve. Great program. And free. 

Ive had the full version multiple times since its included with their cameras. Ive always sold it. The free versions is just fine.
It runs very smoothly on my girlfriends old, old, old base model MacBook Air and my base model MacBook Pro.
Both running Iris graphics, no dedicated.
So it wont run on everything, but nothing super required. 

Yeah give it a shot dude! Again I could be incorrect as I don't use resolve and am going off my memory. But on the website there is a super long list of comparisons and it looks like you are getting a super video editor, great color correcting platform and all for FREE. Considering you are wanting to save money (that could go toward better lens/lighting/equipment) I'd do this for sure

Thanks! That Davinci Reslove looks great! I don't plan on exporting anything bigger than 1080, the only reason I'd be using 4k at the moment is for editing options.

Premiere Elements would be better than photoshop. BUT I believe DaVinci Resolve is a free download. I'm not sure of the drawbacks but I believe you can't export a 4k video, other members on here can chime in. But maybe download Resolve before buying anything? Could save you money and I think you'd get a fuller featured video editor than Elements.

I've looked at getting Premiere Pro CC, but it would be out of my budget to get it. I currently just have the Photography sub from Adobe, Premiere would have to be got as a separate program and I can't justify the cost of that at the moment. This is why I had thought about a cheaper standalone program instead.
 
Would Premiere Elements be a better choice than using Photoshop? I could pick it up fairly cheaply
 
I probably should have mentioned that I'm trying my best to keep costs down as this is purely a hobby.  I've been looking into using cheap vintage lenses with the GX80 and I'm delighted to see that that seems to be a popular option.

I'd say bad, since it's not designed to edit video. Kind of like editing stills in Word, which you can. If you are serious about video, sooner or later you'll have to learn to use editing software -not power director nor elements-. Since you are already subscribed to Adobe CC, check how much would it be if you included Premiere CC. At first you may be lost, but that steep learning curve has to be endured and Premiere is as standard and easy as editing programs can be. The upside of this is that, since the concepts are the same, adapting to a different version o program is not that hard.
Yes it would be present. Depending on the type of noise, the resizing could improve it or not. If you de-noise first and then resize you could get good results since denoising usually softens the image and the resizing would increase the perceived sharpness.