Hmm, I don't think Firion had much of a personality. Don't think they had gotten that far in the game series yet. I'm not so sure about Bartz either. But besides those two, I'd probably say Tidus. Just like everything else in FFX, I hate him. One thing is his incredibly stupid personality, but did they have to have him wear that ridiculous outfit? I mean, sure it's good to be innovative when designing new characters... but Tidus' clothes were just silly.

Squall kicks ass because of his major development of character, same with Cecil. Zidane rocks because he was a generally nice guy. Locke rules too, even though I wouldn't agree with the statement of main character there. And you all know about Cloud, awesome story there.