Neat idea for after zeta, this will make same characters semi unique compared to others same charact

The issue with diversity right now isn't lack of choice, but lack of balance. Although it is much better than it once was, we still see the same ~10 characters in the top of the arena. Some abilities are inherently better than others, so even with another layer of upgrade, you will likely see the exact same choice across multiple teams.

If you do manage to balance the abilities so that each choice is equally as good as the next... well... wouldn't everything feel the same again? That's the paradox between balance and diversity.