Frankly there's a lot of BG3 that is already pretty close to my ideal CRPG.
So the things I'd wish to see addressed in a hypothetical BG4 are pretty much the same I'm currently hoping to see changed or improved in BG3.
A control scheme that doesn't make me wish for an armed conflict with Belgium in the near future, support for a larger cast, putting aside the fairly redundant idea of "origin characters", a world with day/night cycle and and sense of passing time not perpetually stuck at noon, a better and more flexible implementation of verticality, some occasional tweak in terms of visual and aesthetic, etc, etc, etc.
+1 to this paragraph.
