I have a 4K and a 2.5K
4K low light is terrible, FPN isn't terrible especially at 200iso-400iso, now having options of ProRes HQ, LQ, 422, Proxy makes a huge difference in media storage requirements so its not longer a media beast.
2.5K is better in low light, however still only 800iso but does hold a lot better, no compressed RAW means its a media hog at RAW, The crop factor sucks, but once you get use to it its kind of nice when you want to shoot long lens stuff a 135mm becomes a 300mm basically, but sucks for wide stuff however still possible. With the speed booster that all goes away and your back to a s35 anyways. Just remember its passive lens mount if you go MTF.
Both require a rig to make work so I am assuming you have already thought of that and are prepared for it. They need a battery system and monitor more than most cameras.
Black and white requires more attention to lighting, you can use any colour temperature of light and mix them but you need to create more contrast and difference in tones on screen when there is no colour to separate things. I would bring just as much lighting as you normally would and treat it the same making sure you get great contrast and great range of black to whites through your images.
I suggest an old vintage set of primes, they will have character and some flare but they will give you a wide range to learn with and make you work within the limitations of the lenses so when you switch to higher quality glass you'll have much more freedom.
If you're looking for zooms main thing is make sure they have a constant aperture. Nothing is more annoying then losing a stop or two at the long end of the lens.
The camera was the lytro, https://www.lytro.com just search on NFS if you want the article.
The technology isn't here yet to do it in video, let along HD or 4K. It could be really cool if it was possible in time though, give it a few years. I think this will lead to an even lazier bread of film maker though. You will be able to make decisions in post and not have a worry on set which isn't right.
There is a plethora of companies that make v-mount batteries and chargers and even AB to V-Mount adaptor plates if your 1x1 already has AB plates, this route is cheaper and performance is just as good I think. Benefit of AB is the looking 3pin style connections. Most of the batteries are similar though in performance.
Choosing a frame rate ahead of time is important for using framing to tell your story. Shooting for 16:9 then cropping to 2.35:1 can cause weird frames or unplanned importance on things or even missing out on a subtly placed prop or similar.
As far as shooting 16:9 as a standard that is defiantly true, 2.40:1 was developed so theatres could offer something that the home viewing experience couldn't, which is why TV isn't shot that way and cinema is. Also why you rarely see comedies shot that way, we perceive 16:9 to be more realistic and real life and 2.40:1 to be more story telling so it can very much change the feeling of your movie.