Garm Bel Iblis comes in a close 2nd, IMO, and was also the only flag officer in the New Republic who had a chance of fighting Thrawn to a draw. Talon Karrde was another character who received a fair bit of development in the EU novels.
I started reading the Yuuzhan Vong novels, but quickly got bored with them. IMO if you can't finish a Star Wars story in a trilogy there's no sense writing it. Perhaps 3 or 4 separate trilogies covering different parts of the Yuuzhan Vong invasion would have been better. As it was, it was more like a never-ending Star Wars soap opera.
_________________________
Phil
Hey politician, can't believe a word you say
Almighty media, whose truth d'you sell today?
Watchdog of justice, who keeps their eye on you?
Con man, song in hand, who you singin' to?
The more I get to see, the less I understand
I'm just another ordinary man.