The superpower I would have is the ability to use magic. The way I would use it for good is that I could bend someone’s will. I would use this on people who have become evil to turn them good. (Sidenote: I would go to the white house and bend Trump’s will so he will do good.)
Another part about being able to do good is that I would be able to catch crooks. This is true because I would be able to sense them coming and then I could use my aura energy and will it to become handcuffs.
A 3rd reason that I would be able to do good is that I would be able to use my powers in a hospital. I could heal people easily without having to use medicine which means there would be more for other hospitals.
So what sort of magic? As in, would you say a spell, wave a wand, simply think it?