Let me bestow some sagely game design advice.
All boobs that go up, must come down.
I hate Tri-Ace games for attempting "mages" in their active time battle concepts. Fighters were always more damaging. lol, "waiting" to cast a spell in ATB systems, it's funny.
Valkyrie Profile 2 fell victim to having all unique, story characters being better than the rest of the lot that you can find. While not surprising, it takes away the sort of element of surprise and customization of the whole deal. Again though, mages generally weren't that good. And oddly enough, fire protection was more useful than any other element...
The Tales series has been pretty good with party balances, Abyss being one of my favorite for this. Only 6 members, but each with interesting strengths and play styles. I think Radiant Historia covered this well too. To the point, actually, where you ask "do I want 'x' power-up for the party, or 'y' power-down against the enemy? Or do I just wanna fuck up enemy with powerhouse attacks?"
Fails: Chrono Cross and Suikodens aren't good balancers, and can't be either. Too many characters.
Baten Kaitos and Chrono Trigger (and Cross) did an interesting innate element thing with characters that made certain ones more valuable than others at certain times. An interesting way to "balance" their uses.