She was based in Detroit in the 80s when the Justice League HQ was in that city.
If we're talking just female superheroes in general then Sue Storm was way before Rocket. Wonder Girl (Donna Troy) was a mother at one point and Spoiler too if memory serves, but I don't know their current status due to the many reboots & retcons.Female superheroes aren't exactly popping out kids either, we don't need a black female character to be the first or one of the first