I'm thinking about re-rolling soon... being a level 42 fireball-chucking badass is cool and all, but I'm anxious to try something more up-close-and-personal. Not to mention doing any of the other questlines at this point almost feels like cheating because I'm so powerful. I bumped the difficulty up to expert a while back but it generally just means 1-2 extra blasts to kill something - though it does seem like I'm running into larger groups of enemies... maybe I'm imagining that part.
FWIW, I'm having the same problem with an up-close-and-personal guy. I'm on expert and it's still pretty easy -- although I did run into a couple of tougher battles recently.