It's always been a pet peeve of mine when in science fiction and some fantasy when people seem to have figured nearly everything about the fantastical elements of the setting with absolute certainty and seemingly at no point in all that figuring out do any new questions crop up. For whatever reason that's one area I really struggle to suspend my disbelief in and it happens all the time so it's nice to see you just flat out say there's a lot that just flat out isn't known yet.

Honestly, it could be cool if you run with the idea of the schools of magic. Maybe something like those 5 schools of magic are the ones that have thus far been officially classified. Not that anyone thinks that all arts fit within those, just those are the only ones well enough understood to properly group together into categories. Or maybe those are the broad strokes primarily used when teaching about arts leading to a common rookie mistake of trying to overbroadly apply that knowledge to entirely inapplicable situations.