Meh. Thou shalt not speak ill of Xenogears. For it is good. Most of the characterization issues are just from a relatively lacklustre translation, but, you know, I'm sure Square was very tentative about bringing Xenogears over in the first place. I mean, it does have very religious themes, something that the American audience has trouble dealing with.
At any rate, Mog is sweet, the whole cast of FF6 is awesome (they somehow managed to develop all of those characters fairly well. Not great, but hey.) Vincent is cool, and so is Auron. Some of my favourite non-Square characters, though, would have to be the cast of Earthbound (Ness, Paula, Jeff, and Poo! Whee!), Viktor and Flik from the Suikoden series (I and II, at least, III AND IV NEVER HAPPENED) Other sweet RPG characters are slipping my mind for some reason.