I know that some of them wrote episodes of other Star Treks, though none of the big ones. I never really got into Battlestar Galactica, but I could one of these days... I did see the first pilot episode...
Ira Steven Behr has worked as a writer and producer on such shows as THE 4400, ALPHAS, and, currently, OUTLANDER. Michael Taylor has worked as writer and/or producer on VOYAGER, BATTLESTAR GALACTICA, THE DEAD ZONE, DEFIANCE, and is currently a Co-Executive Producer on TURN: WASHINGTON'S SPIES. And those are just the two that immediately come to mind.
Robert Hewitt Wolfe is co-exec producer and writer on Elementary. René Echevarria is exec on Teen Wolf. David Weddle is exec and writer on The Strain.
DS9 was the biggest Trek for me! And Behr, Moore, Echevarria, Wolfe, Beimler, Fields all wrote for TNG.
Do you want to imply that Teenwolf is a worse show than DS9? No seriously, yeah, some shows like the 4400 got cancelled and I don't think they had a proper ending. I found that sad too. I never watched Defiance and don't know many of the others - except Teenwolf.
Ron Moore on BSG, of course, and then Outlander (loved the first half of the first season). Cool story. During the last season of DS9 I sent a baseball and a sharpie via FedEx to Ron in care of Paramount. I asked if he would sign the baseball and also get the rest of the writing staff to do so. I enclosed a second prepaid FedEx envelope to send it back. He did. Ron is aces in my book!