All of them.
Altought they could be a little different.

Squall having a smile during the game, talks more to people.
Zell not being a chicken wuss.
Irvine not being a pervert, not loose his cool.
Selphie being more complex.
Rinoa a bit less pale, blue eyes, any other natural hair color.
Quistis not being confused in her emotions.

They could all use alternatif colored clothing to upgrade their style.