If AvA had more use, and there were more GV setups in FSO, I'd be with you completely on this. But really, this seems like putting the cart before the horse.
Since there are no allies vs axis in the MA's, that leaves scenarios as your primary argument here, and it SEEMS that when theres a GV setup, the allies tend to have air superiority. North Africa would be an exception, and the axis might (just took a big AP history exam, feeling too lazy and tired to check wiki) get a good GV buster with the Ju-87G-2 for that setup as well, although the axis are also lacking in the AA department in that one too (if we're being historical).
We get more GV use, hell yes, I'd want the crusader AA.
And I certinally want the Panzer III, and I don't know about justifying it above EVERYTHING else, but I can certinaly justify it above the Crusader, and perhaps even most of the other GV stuff we could add, at least from a non-LWMA-centric view point.
Panzer III lead the German Blitzkrieg across france, Africa, and Russia. It would be able to fight the T-34 without requiring a strech like letting Panzer IV F2's into an EW scenario, and depending on the cutoff date for EW, even the Panzer III L might make it in, and would be the Panzer IV of the EW arena (T-34 would become the Panther, and the KV-1, if we ever get it, would be the Tiger I).
Also, StuG III.
Anyway, off topic there.