Maybe something like a fireball you can shoot out of your hand, for a reference to this fireball you could look up waltz of the wizard.

Maybe invisibility to enemies… and perhaps disable gravity for enemies…

A great game with a lot of interesting ideas for loot and magic is Legend of Dungeon, though you don't have mana and only get magic tomes that you can use. The tomes do all kinds of things, but you never know what they're going to do until you test them. It may be magic missile, lights, or summon an ally, or summon a dangerous enemy, or summon random things like cats, crates, and stone blocks.

Basically, magic in my opinion should be quirky and strange. It should impact the game in ways like that fundamentally change the environment. Like making tiny storm clouds that are hard to see through. Or filling a room with water. Or inverting gravity. 

maybe you could add a spell that makes spikes come out of the ground

I really like the telekinesis idea. To add onto it, maybe you could use those gauntlets to control weapons like swords from across the room. That way you could hit enemies from far away. I was also thinking about a necromancy mechanic, as that was always one of my favorite kinds of magic in these types of games. Or maybe a kind of aimed spell, like arrows or meteors, that rain down from the sky? Familiars and orbitals are always cool too. Overall, I really like where you're taking this game though. Believe it or not, Dungeon Train is my favorite episode of my favorite show. I have been hoping someone would make a game about it for years.