Number 1 is not tough at all: Squall is definitely my fav character of all times. He begins being "Mr. By the Book" and reaches a point where his whole motto is questioned and he starts to act rather than react to what happens around him. He doesn't like being in teams, but when the whole responsability of the Garden (and the students) falls over his shoulders, he just sucks it up and does what needs to be done. He might not like it, but he still does it, and I think that is something to admire.

I think second place would go to Kefka, the best villain FF has. He's a selfish, derranged, kill-crazy bastard with a very dark sense of humor... like the Joker but with a more suiting outfit

Third would go for Yuna AND Vivi. Both of their journeys are both sad and joyful, full of self-discovery and of bonding with those around them.