One thing I like about BLACK LIGHTNING is that it uses several DC concepts. It might not be in the Arrowverse, but it is in the DC verse.
The 100 was a criminal operation that was introduced in the Rose & Thorn back-up feature in SUPERMAN'S GIRL FRIEND, LOIS LANE, in the early 1970s. And Lois eventually teamed with Thorn to go against the 100. There were a lot of crime groups introduced at that time, including Intergang and the League of Assassins.
We also have Peter Gambi, who's a super-hero tailor. His brother, Paul Gambi was a tailor introduced in the 1960s and he provided the costumes for the Rogues Gallery. The guys on THE FLASH were actually paying homage to one of their fans, whose letters appeared in Flash-Grams--Paul Gambaccini. Paul was quite active in comic book fandom and then went to Britain where he became a leading radio personality. He's always been openly gay and active in the gay community, so it wouldn't surprise me if his comic book alter ego was also gay.
Jefferson Pierce lived in Suicide Slum, which was the ghetto neighbourhood that Jack Kirby established as being in Metropolis, when he was doing SUPERMAN'S PAL, JIMMY OLSEN--which tied in with the Fourth World titles. Since Jack brought back the Guardian and the Newboy Legion in those stories--via retroactive continuty one can assume that the original Guardian (Jim Harper) and the Newsboy Legion were in Suicide Slum. That nicely fits with Jefferson Pierce who was essentially on the same mission as the Guardian--helping inner city kids against the crime bosses.
And as Jefferson was in Metropolis, that allowed Inspector William Henderson to appear in the stories. Bill Henderson first appeared on the SUPERMAN radio show in the 1940s--earlier I mistakenly said his first appearance was on the TV show in the 1950s, but he's been around even longer.