As far as air goes, I don’t like the idea of a sniper taking out a P51, that just seems quite improbable. An MG42 I can see. I also can’t imagine an M1 Garand nailing an ME109. Could it happen? maybe, but probably not.
Again I see it as more of a playability issue. Is it realistic? No, not even close. Heck really planes shouldn’t be in the game at a such a small level. However, I shouldn’t be completely screwed over just because I’m not using dedicated AA, which is otherwise a bit of a waste if my opponent doesn’t use aircraft (perhaps this is where a sideboard comes in… :).
It seems to me that these rules are encouraging a more defencive game and creating an environment where you want your infantry spread out - that way they’re less prone to enfilade/grazing shot, and can also perhaps get in line with a plane to help bring it down.
I didn’t get to play a game sunday with the rules, but I hope to some time this week to try them out.