I think having some characters being unusable like in Melee is better than having some characters being overpowered. Kirby's UP? don't use Kirby, forget he's in, leave your emotional attachment to his games at the door with your emotional attachment to any other game not in Melee, easy. Kazuya's OP? God help you, someone's gonna choose Kazuya anyway, and the internal fandom politics will never allow a ban. I'd rather have 70 Melee Kirbies in an 80 character roster than 1 Brawl Meta Knight.