Seeing how this is, at least partly, a role-playing game, how about keeping track of player stats, kind of like a trophy page for the characters.
I see this as two fold:
- Stats for each character
- Most powerful enemy vanquished
- Most damage dealt
-
of Characters downed
-
of matches
- favorite partner (so character
- favorite power
- etc.
- Global stats
- Favorite character
- matches played/won/lost
- toughest team beat
- Best PVE/PVP ranking
- Most perfect games (matches where player took no damage)
- other fun stats
I really think this would be a great addition to the RPG element of the game.