DC's top black superheroes at the moment are:
GL John Stewart
Cyborg
Mr. Terrific
Black Lightning
They seemed to be interested in giving Vixen that push for a brief moment but that seems to have ended. And I couldn't tell you what Steel is up to.
Black Panther is still a top dog in the Marvel comics universe and Miles Morales still gets shine but Marvel hasn't been pushing Luke Cage like they used to when Bendis was still there so he's not a major player anymore and honestly Storm hasn't been A level in a while either. They have made her a supporting character who really hasn't done much for a couple years now in the X-Men books.
Falcon has lost a bit of his heat too from when he was the New Captain America, leading The Avengers and at the forefront of event series.
I'd argue the order is
Black Lightning
Cyborg
Terrific
Stewart
Stewart
should be #1. And Terrific
ideally should be #2... if not p4p #1 as a non-legacy type originally concept (correct me if I'm wrong on that).
Buuuuut yknow how it is with white ppl..
Marvel isn't much better in execution. A lot of luck with Bendis adopting Luke Cage and creating Miles Morales.
Dr Voodoo, Blue Marvel, Spectrum, Storm, Bishop, Cloak, Nightrasher, Prowler, etc criminally underutilized.
Tho I guess you can argue they (Marvel) have a greater number of known ones within comic circles... without getting too obscure