I think it is gamey (or at least silly) that a commander would gain TONS of actual air combat experience just from ground pounding.
Not entirely. Even though it is valid point that it does not give you real air combat experience, it does give you flight hours + spotting experience.
Spotting unit from airbourne is not that easy. Spotting ground units would also give you some practise how to pay attension to surrounding area which would mean benefit even in air-to-air combat. Spotting your target well enough can be greater advatange than having your entire flight full of combat aces (in terms of kills) with not-so-good spotting experience.
Also, it gives the commander some practical experiences how to command while flying and so on. No matter how well you're trained or how skilled you are, having no idea what you're doing can be fatal in combat.
so your fighters will typically be hurt badly, which is more realistic.
Depends on the target. Unprotected (in terms of AA) soft column can be destroyed even with machineguns from airbourne without any real threat, considering that you can be strafing with 400km\h+ speeds from above, or even slightly protected convoy is still fairly vulnerable if the SPAA vehicles are knocked out, and spotting a vehicle where tracers are flying from is fairly easy.
If it's fixed AA, then it's another story. You might be able to do some high speed low-level sweep around the area but the odds are, you're going to get hit enough to be forced to return to base which would possibly result in irreparable loss. Or crash land. Or simply go down
