If you do continue to develop this, I cannot stress the need to reduce the requirements on the spellcasting side of things. 3rd level spells from two lists requires a serious commitment (Wizard 5/Wu Jen 5 gets it the earliest) if you don't want to use early entry tricks. Being 5 levels behind on spellcasting ruins your spell access compared to just going straight caster. Even the 3 levels lost for Mystic Theurge amounts to a price that's usually too high.
Actually, that was a typo. That shoulda been 2nd level spells. Woopsie.