I like the *assumed* patch notes a lot and cant wait to try them (especially regarding the IL2). That being said, it would be nice if AA was in general more effective.
For example, if you have a m5/ostwind in the area then the plane should be shot down more reliably every pass (50-75% chance as elchino7 suggested), the upgunned 222/m3 should have a ~25% chance per pass, and the tank gunners should be left as is.
To increase the risk/reward of it, if a plane is shot down, it should prevent future planes call ins from coming in (or at least significantly increase the cool down) to reward the defensive player for having AA, and prevent the offensive player from just blindly calling in plane. *note: this "shot down bonus" should not apply to recon runs.
Well, according to leakz, Quad AA will have more damage, 80 to 120.