This is just common sense. The current balance system is a joke when there's 6 horse crossbowmen and they're all on the same team. Or when there's 20 cavalry out of 100 people in the server, and 16 of them are on the same team.
I honestly think you'd have more balanced teams if you just unlocked the auto-assign teams, and took off the balance system. I know I'd play it more like I did when I pubbed counter-strike, if one team is getting walloped I'm going to join that team and try to help them out. Well maybe not with the current multiplier system, but if they change the way XP/gold works in the future, this may be doable.
They are public servers after all, and pub stomps are fucking lame.
Balance (IMO) should work like this:
Try to balance people by banner, but only if you can balance the classes and level of player first.
The current balance system feels more like "stack one team until they hit 3 wins, and stack the other team until they get 3 wins"
Disclosure: I'm a cavalry lancer, so no, it's not just infantry complaining.