I'll try to answer these to the best of my knowledge. Keep in mind that I am not a regular DCS player. For the longest time I used it to fly mock patterns in the Huey to practice for my actual civil private flying due to the flight model. Since then I've switched to XP12 which in my opinion offers an even better and more realistic rotary experience with the R22.
I have a 4090 but a 3090Ti should do just fine. In my experience the game remains CPU bound and I'm on a 7950x3D so I don't know if the GPU is going to make much of a difference between those two. As far as I know, there is no OXR layer with the BSB, everything runs natively through SteamVR runtime so I haven't made any attempts to mess with that. So that means no Foveated Rendering (fixed nor dynamic). But the picture to my eyeballs remains clearer on the BSB than the Aero due to the chromatic aberrations, color shift and mangled distortion profile that has plagued the Aero since VB 3.5. The picture on the BSB is just crystal clear without any messing about.
I haven't played with any custom resolution, the default has been perfectly clear. But the sweet spot on the Aero can arguably be wider however the stereo overlap is much greater with the BSB allowing for a much wider 'perceived' FOV even though it's a hair narrower horizontally. 75hz is what I play on and I haven't had the need to go 90hz yet.
As the work week slows down, I plan on dusting the puma and I will give DCS another run and see if I can add more color to that experience but let me know if there's anything else I can help answer. Cheers!
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