As for the class; hard to say (at least to my inexperienced critical eye). Metamagic can be very powerful, but losing caster levels is obviously quite a hit. I suppose that, since not having this will not prevent abusing metamagic if so desired, and given how nice the concept is, I would probably call it done well. I especially like the idea of removing metamagic from a spell; just imagine the reaction from an arcanist seeing his magic warped before his very eyes!