You could go with a 2.1:1 aspect ratio screen where 16:9 content would be proportionally be as big as 2.35:1. But then again you'd always have black borders no matter the content(unless there are movies in 2,1:1). But some people swear by this aspect ratio due to the proportionally more correct size for 4:3 and 16:9 content. No matter what you choose, 1.77:1, 2.35:1, 2.1:1 or whatever there will always be a compromise in one way or another. You have to look to very expensive solutions to get rid of all the problems - 4-way masking and Lumagen scaler, anamorphic lens etc -very expensive stuff. Also think about that quite a few movies implement multiple aspect ratios with IMAX scenes and so on. You can't really win.
My personal solution was to buy the biggest 2.35:1 screen my room would allow and then sit relatively close to it - movies it's really epic mode activated and 16:9 and 4:3(Star Trek TNG etc) content I watch is still big enough to get a cinematic experience. I optimised for movies basically. I watch a lot of series which is 16:9 but the size is fine due to that the screen can't be taller due to the room. So I'd say if you go for 2.35:1 then go the biggest you can. If you're coming from something like a 100" 16:9 then go for something like 130" 2.35:1 to not get disappointed with less wide but taller content.
I see now that you are looking at quite big screens which is the way to go basically if you have the light output. But also think about that such large screens which are not AT will affect the sound quite a lot. I went the other way where I ran non-AT before and I'm now running AT. The sound is quite improved imo so think about this that you'll have a very large reflective surface. But there is a significant difference in sharpness and light output so I understand your move there. Everything is basically a compromise in one way or the other so choose what's most important to you.
Room| Treated | Sound| Front: Ino Audio i32s, Center: Ino Audio i16s, Surrounds: 6 x Ino a2, 6 x Ino a1, Subs: 6 x Ino Infra-Y|
Picture | Epson TW9300, Seymour Center Stage UF 130.4" retractable 2.35:1 |
Electronics | Arcam AVR390(Dirac Live), 3x Ncore nc400 monoblocks, Emotiva XPA-2 Gen2, EP4000, Panasonic UB700, Allo Katana + Isolator 1.2(Roon bridge/DAC), ATV 4K |