Now there's another, in which people get powers at random.
So the heroine has life draining powers. So I'm trying to figure out the details of her personality beyond the two I know are needed for the plot: she finds her power disgusting and repugnant, especially after she accidentally drains someone who helped her, and she is willing to listen to an authority who can train her.
And I bounce between "quiet, retiring, shy" -- what an obvious personality for such powers -- or "bright and bubbling" -- what an obvious simple reversal. It may not be an obvious connection, depends on how I depict the power and the personality, but when I start from the premise of "opposite". . . .
Maybe I should just generate a bunch of secondary characters by random personality/powers generation and hope that will break me free.