Hello. Just decided to join in.
We on Sukhoi also doen't have much info, just as you do. We hoped that patch will be out by friday, but developers still got some bugs out there deciding for us to wait

Just as you've noticed, seems there is nothing much planned in the actual patch version that is not already implemented in beta.
As they said, there might be some tuneup of the lighting since there was much whining about too bleak colors that creates effect that everything is in some kind of fog - just everything including cockpit. Seems colors will be set just a bit back to saturation, but it is only my thought.
New cockpit and external sound effects sounds nice, but it looks there are no enough samples to compensate wide spectrum of the engine RPM sounds. Though for my point of view that's better than initial ambisonic recordings. In the final patch version they said more samples will be implemented. We'll see.
Hope game crashes (for me it looks memory leaks) will go as well. Seems it is the most info we on Sukhoi have