Aqutalion
That's odd, I remember having the opposite problem last time I played it. Lufia kept getting ahead of everyone else, and it bugged the crap out of me because I don't like the party levels to be unbalanced (OCD, anyone?).
I know that in some games, different characters need different amounts of exp to level up. That might be the case here.
lol im totally ocd about it too, since lufia is my favorite in this game, well for now, and its driving mee NUTS!!!! oh if anyone wants an snes emulator, i got that and lufia I and II at romnation.com i think, AND without any annoying "vote for my site" popups