Chalk up another vote for Kyle Katarn. Han Solo/Lando are the strong runner-ups.
I like Kyle because while he's a powerful Jedi and an amazing lightsaber duelist, he still has a gruff, cynical, and sarcastic demeanor. I feel that it gives him more personality than most Jedi and he makes a great contrast against the rigidness of the traditional Jedi Order. Jolee Bindo was similar in this line of thought and preferred to do things his own way rather than sticking to a strict set of codes. "Abilities are not inherently good or evil, it's how you use them."
Han/Lando also have similar personalities to Kyle, but without any of the force stuff. Star Wars movies and books tend to just tell the stories of Jedi and Sith and other force-sensitives while ignoring the rest of the population. Lando and Han are the representatives (so to speak) of the commoners. They're very interesting characters, and they give an insight into how the non-Jedi population lived and thrived.