Hmm that's a hard one, but I do enjoy very RPG-like classic systems like old FE's with nature magic and light/dark magic

idk if it counts cause, its alchemy but the fma one

Now that's a hard one.
I do like the force with how loose it is.
However I do like some more hardcoded magic systems?
I think I'll go with the force here.

the one involving mike idk lol

I think the arts system in Arknights is really cool! Tbh it's the only one I can think of atm

dont know if it counts but projmoons whole EGO stuff is neat

Probably Devil Fruits in One Piece. I don't care if it counts or not.

Horror dystopian at this point it's not even a magic system but technically losing sanity to gain more is nice