In terms of just Earth saving stuff? Stopping a murderous robot since there tend to be a variety of murderous robots around. Or maybe the heist dream because it was set up by us but memory worms were used so we didn't remember that so we went through the motions of a bank heist only to realise we were helping someone right something they regretted as they were dying and gave them time together.
Nah, wasn't too keen on being an empress like that. Too stagnant compared to the travelling through time and space.