I like this class. A few minor comments:

First, there is a typo in Magecraft. There should be a space between "cast" and "arcane mark."

I also agree with Stycotl's comment about giving them a progression like that of a wizard.

Finally, it might make sense to let them customize the spells they have access to. Perhaps something similar to the ability given to the Warmage or the Dread Necromancer.

Not sure fluff-wise what to call this, but maybe at certain level they get to pick one spell from the wizard/sorcerer list of a level they can cast and treat it like it is on their class list? This would also reduce the total number of dead levels. Not sure what levels to put this one though.