Could not agree more.
Vixen has a unique look, interesting and versatile powers, and a personality and backstory that is just BEGGING for development. I can't think of one damn reason why DC can't see her potential and make every effort to tap into it.
If they don't think she's ready for her own book? Fine. I can respect that. I understand Storm is JUST NOW getting her own ongoing after decades of being one of Marvel's most popular women. But at the very least, she deserves to be a prominent character in a team book somewhere.
Like others have said, she'd be a fine addition to the Justice League. She'd also be great on Birds of Prey. Opportunities for this character abound. I really can't think of a good reason why they wouldn't give her one.