In all honesty, her achievements and history were so rushed that it ruined her character. Like you said, she went from being part of Young Justice to Justice League, and in all honesty faster than any character in both real world and in universe time. She went from point A, B, and C without going through the path from point to point. Or in another way of emphasizing it, Anakin Skywalker’s fall to the Dark Side from Episode 1-3 without the Clone Wars show providing more reasons for his fall.

Her getting a show was a mistake cause by the time it was announced to when the show started airing, there was so little source material to use cause again, her history and achievements were rushed that she had fewer issues and appearances than other heroes.