--Just hopping in here to say -- and please take this with a grain of salt because I love this movie but also haven't seen it in a few years and so am likely forgetting nuance -- that for me the movie works in part because it isn't just a total role-swap (the superhero is not the antagonist of the story), and also, when it comes to "getting the girl" and the romance storyline, Megamind has one of the most savage dismantlings of the nice-guy trope that I can think of, it is wildly satisfying for that.