I imagine this should be clear to anyone, but it probably isn't.
Any time you get a "GV Mishun!" it is 3/4 flakpansies, a couple tanks to protect the flakpansies, and a couple M3s.. that means the flakpansie is overpowered.
Granted, it isn't anywhere near as bad as it was back in AH1, when the flakpansie was the best anti-GV, anti-air, and anti-town/field GV... but the simple fact that the "anti-air" GV is present in numbers in one "mishun" that are larger than it was present in WW2 should be telling.
Perk it. Big. Or greatly reduce its efficiency against buildings. One flakpansie can roll up to a town and trash it far more quickly than a company of our tanks can, which makes for some really strange gameplay.
For instance.... why bother with the IL-2, 190F-8, or Hurricane 2D? All of them suck against flakpansies, and that is what they are going to run into 80% of the time. Instead, use a flight of level bombers and carpet suicide-bomb the GVs! Garbage in = garbage out.