On the Slaver, my main interest is in seeing another variation on the crew / gang / followers / holding model (and, alongside that, Pack Alpha / Leadership / Frenzy / etc. as a move for using your peeps), since I really like those and would be interested how one would look that was explicitly focused on victimization.
Color wise, I'm remembering this story about a character Tony played in one AW game, where an important female NPC was going to abandon him for being a horrible human being, but he sat her down and said: "It's okay, baby. It'll all work out; just hang in there" or something like that. Totally twisted and showed why people stay in bad relationships. I wasn't there for it but it was on my mind.
Seems like the character type could be pretty open about how and why the Slaver victimizes people -- is it drugs? sex? emotions? physical chains? beatings? they have the only access to food or medicine? You know how Hedwig keeps all the passports of the Angry Inch band members? Like that. Total Slaver.