On the gay thing, you said your patrons squick over that. Where I come from we have a saying that goes back a long way: "It's not gay, if Mistress orders you to do it." Words to live by. I could add, it's not female "dominance" if the male enjoys it all or wants it all. That's just dress-up man-servicing. Maybe that's too hard core of an idea?
You are giving the players a choice, which their male slave characters definitely would NOT have. I think that's more than fair.