My suggestion:

Why EK? Why not Monk/Wiz/Enlightened Fist with Carmidine Monk feat? Since the Litch already has obnoxious things that happens when he hits you, let's let him hit you a LOT, channel spells through touch attacks, and in general, be onboxiously nasty.

Not as obnoxious as something like a straight Wiz/Iot7v/AM or Wiz/Incantatrix/AM... but then again, we're not wanting a TPK.