I played around with the concept of other revolting powers, but concluded this one was necessary.
And then bounced around the idea, thinking that at a later point, when she can control it and send it elsewhere as well, of a time where she draws on some immensely large population (that of the Earth?) to feed to a single superhero so that he can save the world. . . and realized after more than it would make crime fighting a not particularly amusing farce, since she could drain the villains and feed it to her teammates.
So, some restrictions. Perhaps the world-saving would be possible, with some assistance, but restrictions are necessary. Ethical ones, perhaps, but if she gains enough control (and it's essential to the story that she do so), it would be hard to keep her from having no ethical qualms, since she could do it without injury. Or perhaps a straightforward power limit, of distance, perhaps (use a device or a superpower to evade when saving the world). Or perhaps it's possible to devise a gadget to protect against it, once you know it's a possibility.
Each of which would lead to very different plot and thematic implications.
Ah, well, still playing about. I don't even know the heroine's name (though I do know that of her love interest!).