On the one hand, yeah you'd expect all of Marvel's magic types to at least make an appearance, and any good Hogwarts ripoff needs a Slytherin around, and Loki's the Slytherinest Marvel character out there, right down to his favourite colour. Loki's also actually done more teaching of magic than pretty much anyone else, having taught both Wiccan and Zelma. (who is also likely to appear as the school librarian, which, if Loki is there, much to Strange's chagrin, may rekindle things there, even tho i am still holding out hope for Raz) the motto on the emblem seems to fit Loki well, too. But on the other hand, if Strange is running it, I have trouble seeing him approaching Loki for it after the whole God of Magic deal.