Speaking of Earthfasts, Keith, David, and Nellie Jack John in the 1994 television adaptation have all gone on to exciting careers.
Also a lot of movies, including the critically acclaimed Clapham Junction (2007), about a day in the lives of a group of gay men.
Chris Downs (Keith) didn't do much acting after Earthfasts, but apparently he has become a model. (Doesn't really look like him, but that's what the Internet Movie Database says.)
Bryan Dick (Nellie Jack John) worked in music for awhile and then returned to acting, with many guest roles in tv programs like Clocking Off, Blackpool, and Torchwood. He has played several gay characters.