I personally prefer it where stories have some sort of pseudo-science, or at least a framework of rules, to follow when someone gives their character power. It prevents a lot of issues from creeping up; and I know this because a lot of stories I used to participate in that involved magic resulted in a lot of confusion.

With this in mind, though, I came up with a Spatial/Cosmic-class (not sure which, probably Spatial) character, or rather, have one I can re-purpose for this story, whose power involves overturning certain laws of physics, as long as she physically touches something, even though her own physical endurance/strength is really no more impressive than a human's. I enjoyed the character, because there was cool stuff she could do, and I could get away with causing comical accidents when she messed up regarding her powers (No one else but her was harmed, of course), like cancelling out the friction of her shoes by accident. I don't know if she would be regarded as OP or not, though, because if she learned to use her powers, well, she would probably score pretty high on the power strength scale.