Eh um, I kind of disagree with you. If they decide to add more schools, than you would need more training points to learn them. But whatever. I have been thinking about these as well. Here are a couple ideas...
School of Chaos: sort of a mix between death, myth, storm
School of Order: sort of a mix between life and balace
School of Obivion: This school is the school that consist of nothing. These Wizards are good in depleating Damage, Resistance, Accuracy, Pip Chance, those sort of things. Cross between Myth and Storm