You just need to realize, that you are not a full mage. With 3 wpa and some science investment you end up with 7-8 mod wpa. That is enough to fireball people down, give max duration greed, expose thieves, etc. These spells usually eat up mana from full mages. Undead Mystic is a synergy monster that you need to incorporate into a kingdom strategy.
edit: And if you get chained and need to get rid of a few wizards, just relaese them into peasents and cast townwatch.