Of course, it's worth noting that whether you win or lose would be mostly based off of your personal writing skill, how well you convey characters, and the coolness of the story rather than the strength of the opponent's character, since you have complete control over how a portion of any fight possesses and whatever occurs in it becomes canon if you win.  Ingenuity on the player's side can help a weaker character overcome a stronger character.  That said, it doesn't affect my decision to enforce a generally balanced power level at all.