Regarding point 5…Do you mean the terrain morphing that you now see when flying over high DEM mountains? This was one of the worst features of P3D/FSX that I was really pleased to see had gone from MSFS (well gone until the USA update and now worse in Dec 22 update!). It may be the ‘issue’ was always there but was only now seen due to the high DEM but it’s a retrograde step whatever. Again this does not seem to have raised much attention except here:
Only 44 votes (at time of this post) - please add if you are seeing this too.
System i7-10700K/RTX 3090/32 GBRAM@3000/1TbNVME - GPU @ 60-70% CPU main thread @ 44-60%. Locked at 30fps. I was hoping this system may have been enough 
Edit to add some balance: Despite these issues I think this simulator is great. At 4k/Ultra settings I still regularly have my breath taken away by the visuals - hence my (and I suspect a lot of ‘angry’ posters) frustration at the degradation we’ve seen. P3D has not been started on my PC since MSFS’s release.