I appreciate the thought and effort poured into this location and I don't want to just let this one go, but there is a reason why there currently are no formal schools of magic, or even just any sort of formal schools in Avanthal at all. The Vantha do not feel a need for formal institutions of learning since children are usually taught by their parents in the specific craft their Hold specializes in.
As for magics, leeching, voiding, and summoning are a firm no no within the city. Mages found practicing such disciplines are immediately arrested by the Icewatch and taken in for questioning. Remember that the Vantha are more wary of magic than some cultures, and the only disciplines they really only accept are reimancy and auristics, and they take special measures to ensure that these magics cannot be used to damage the city and harm its citizens. Exactly the reason why the city's mages are encouraged to live in the Barracks, both to the mages' protection and containment. Spiritism is tolerated but seen as frightening as it deals with the soul of the departed. Hypnotism, once its true power is truly understood, will be feared by the people and users of this magic can be seen as a potential threat.
People who really want to learn magics would have to go and approach a mage with the particular expertise and ask for an initiation. The screening process is often hard because a mage is almost always a city guard as well, and they go out of their way to make sure that the person asking for apprenticeship is worthy of learning the magic, and he or she does not have any psychological disabilities or mental illnesses that will affect their good judgment. A crazy mage is always one of the most dangerous ones after all, and the Icewatch knows this.