Best character: Yu Yu Liang, definatly one of the funniest ones. I also liked the guy who was at Skeln with Druss, and also in the first Skillgannon book. Can't remember his name or be arsed to get up and go look
The Riaz Nor were ace, as was Helikaon.
As for worst charcter, I don't really have one, but Jon Shannow is just a bible-bashing Waylander with guns so therefore not as cool. Also I never got the whole Skillgannon thing, just seemed to me to be a cross between a few of DG's other character's. That still made it very readable and I really liked the books but I would not put Skillgannon above the others.