Since you're mostly a spell-caster, Sage couldn't hurt. You'll be able to make your own spell upgrades to Adept III (one notch below the dropped and expensive Master I's).
Edit: I hate advising people on a tradeskill class, because if you're into crafting you can barter or earn cash for 'most anything you need.
Edited, May 15th 2008 10:47pm by Calthine