I'm just going to go ahead and say, without even consulting with my apparently cocksharing GMs, that Ghost Rider is definitely far beyond the scope of this game. Nico Minoru, though, I think would entirely depend on the sheet itself. There are aspects of her Runaways history that can definitely be more grounded depending on the avenue taken, though the Staff of One, without limitations in place, is definitely capable of being an aforementioned deus ex magica.