When we’re discussion balance, I think we should separate changes which are strictly about balance, while other changes are the same as introducing house rules. I think we should discuss house rules and balancing issues separately.
Unit bids have been used in classic, revised and AA50. Bids are also a “kiss” principle.
It’s also worth mentioning that most players think that the balance is pretty good. Very few players think either side should get a +$10 bid, and in a setting with ADS, no tech, NOs, I would take either side with $5 bid.
There’s no need for a major balancing of AA50 as such, a few units it’s all thats needed, so unless someone is really unhappy with some major aspects of AA50, the game balance is not a big deal.
I don’t think we should expect a game balance like chess :-)
As long as the balance is not more asymmetric than revised, it’s good enough for all of us who play on line, we’ll be informed if one side starts winning almost all games.
edit:
What I really would like to try, is cash only bids. In this way the original setup is the same, but one side will get some cash so even if i.e. axis are favored in a LL setting and will attack and advance more than allies can defend, when giving allies a cash bid, the axis advance will be stopped, albeit later than with a allied unit bid, and then allies can start to push back axis, if they allies use their extra money wise enough.