[Lewdcifer]

I'm bad at balance so this might probably sound like a bad suggestion, but it's worth a shot.

We all know that Spellthiefs normally have a cooldown on their stolen spells of three turns.
Currently, there's not much advantage to main classing Spellthiefs, and the cooldown imposed on stolen spells sorta make them not so much worth it.

Which brings us to my suggestion:
What if main classing Spellthief reduced the cooldown of stolen spells to two turns (or one)?
This could make them more worth using, and would give Spellthiefs more reasons to be used as a main class.