I think I did the same in my last run-through.
You end up trying to squeeze out every drop of experience from monsters: too bad the respawning ones (such as the ghosts around the desecrated church) give you so little towards your next level, when you reach 20, much less 30!
Still, in the end, it's more about having a variety of useful skills, great weapons, and gold-imbedded enchants.