Really, though, I think that if the 'make your own challenge mode' is put in it should by all means be completely optional (no combos are required to unlock anything) and no games within the mode will count towards any requirements for player file advancement (as in Sergeant, Demon, etc., no matter what you're doing). That way, it's always just for fun and the bragging rights you get out of having a character win while being compulsively an angel many times over, and those who don't want to have anything to do with mixing challenges can easily ignore it.