I'm not saying its not possible, I just think its not worth it. DC is not Marvel, yes there are some unique spots in NYC that spiderman has that the real world doesn't, but we can have that and more with a fictional city. She keeps moving around from one real city to another, its only a matter of time before another writer moves her from DC to Boston again. There is a lot of unique potential that Gateway offers that I can't see DC doing. And sure it wasn't originally hers, but it seems to be mostly acknowledged as hers and if she need to share, Spectre isn't a bad roommate. You can have more than one character operating in a city and even then Spectre and Diana are global. Metropolis and Gotham had time, Gateway needs a jump start.