If I were to write a female superhero for our modern era, I think I would focus on mostly her flaws as opposed to her strengths. Even now as media progresses, female characters are written in ways that leave them flat and uninteresting. While male characters are riddled with flaws and are still considered beloved, female characters hardly get the same treatment. I want to create a female superhero who fits the trope of a character who is aloof and judging, but who, at the end of the day, cares deeply about others and will do the right thing. While there may have been occasions where female characters fit this role, I can't call to mind any specific female protagonists who truly had this character type. What seems to be more popular to me is the existence of a female character who is cool and indifferent, who does a complete 180 and no longer acts that way, usually because of a man but not always.
I would love to write the story of a hero facing a destiny she doesn't necessarily want at first, given the power over ice by a greater force, such as a powerful ancient god. I'd want to encapsulate the story of a woman rejecting parts of her she feels are inherently bad (her own power) and using them to do something good in the world.
While I did initially focus on writing a character with flaws to make a point, as a complex character, this heroine would have a lot of redeeming qualities as well. As a prominent female character, I would want her to be tenacious, not backing down in the face of tough situations or frustrating scenarios. At the end of the day, despite her flaws, I would want this character to emulate determination, even in the face of the worlds strangest scenarios.