True, I don't know Kefka that well, I've never completed VI and can't find my copy of Anthology, Kuja, despite being gay and despite being a whiny brat (like Genesis), still manages to be pretty cool... despite himself.
FYI, I consider Necron to be an extension of Kuja (being formed from his malice toward the world) and think of him as a third form of Kuja.