The wizard still has the basic problem that some spells break the game all on their own. At the very least, I would impose some restrictions on summoning and shapeshifting spells, which are often the worst offenders.

Similarly, schools are pretty unbalanced amongst each other. I'd consider doing something about Transmutation (which has buffs, offensive and utility spells) and Conjuration. Moving blasty conjurations to evocation would probably be a good start.