I’m interested. I’m still fiddling with concepts. How would you feel about a superhero whose power was possession? She would be able to take an intangible form and enter objects or defeated bad guys. She can enhance and animate the thing she is possessing to make it capable of more impressive feats (such as possessing a sword and making it extremely sharp/strong, or becoming a walking suit of armor that can take a severe beating.)

While possessing bad guys would give her different options. Like using their body/power for a limited time, or interrogating their minds while possessing their body. Just as a rule I wouldn’t attempt to possess any currently active bad guys unless they were insignificant. Significant bad guys would need to be defeated first to give her enough time to wear away their resistance.

This is a bit morally grey in the best case, so the character will have to deal with the ethical issues arising from her new power.

If you don’t like that idea, I might go for something else. Like control of plants or super-powered eyes. I like super-powered eyes. :D