Anyone want to listen to me complain more about super heroes? No? Bah, too bad.
Part of the draw of super heroes involves their uniqueness, e.g. they’re the only ones who can do these things, and it can’t be replicated. Well, usually. You’ve got plenty of exceptions, like the Green Lantern Corp, but they all have their own self-selecting criteria for inclusion; ranging from the Corp/Guardians selection process, hereditary powers, inherited mantle, etc. (The Dial Wielders from Dial H for Hero/ Hero/ Dial H, where the only limitation is possessing a dial, are a ton of fun, and a great example of how to do it.) So: in order to maintain the hero’s status as special/ unique, you need to have some way to limit the imitation of their powers.