You're the guy who said he was a coder and needed an artist from the other thread right? I had a couple of ideas in that thread.
So what style of game were you going to make? I don't want to push you into making a game you're not 100% gonna enjoy playing because then you won't enjoy making it. I am happy to throw some ideas out that I think may match your criteria though.
One thing I'd like to see is long induction style scenes, I don't like it when it's just straight to being hypnotized. I'd also like a build up before they'd become a sex slave, like slowly giving more lewd suggestions over time so they get eased in and don't realize I'm slowly changing them. Also how about some not sexual stuff too, using hypnosis to help them and to mess around with them. Maybe together the forum can come up with some really fun suggestions.
Anyway, I'd love to help out with more idea as thing thing starts moving on. I'm not really good at writing but I could at least think up so general plots. Oh yeah, I could help with the art too, I'm not too good but I could do character art and backgrounds. I've posted a few thing here and even though I took a long break from art I'm starting to get back into it and I'm slowly improving.
Well anyway I hope this thing takes off.