It's a cliche, (but one with insight) that a hero going really bad is much more dangerous than the villains. I'm not sure what Kim's evil drive would be, though. Greed? Ambition? Anger? Maybe deep down she blames her parents for making her an over-achiever by their example. It'd be funny if the Bad Kim just wanted to loll around all day in her PJs, watching reality TV and eating junk food to punish her folks. ("Don't you want to save the world, honey?" "Whatever. DANCING WITH THE STARS is on next.")