The obvious thing, then, to do is have the Sim study your spellbook and support you in combat as a free henchman.
Also, which 51-60% of the levels does the simplacrum get? Take for example a Ftr2, Rog2, Wiz5, Red Wizard3,Guild Mage3, Loremaster 5, exactly which levels does the simplacrum get?
Tzarevitch