Good question, there aren't any plans for the far future yet, but the current plan is to stick to mostly a vanilla, becoming a harem down the road. There will also be some light femdom options for players who are interested in that. Looking further ahead than that there is potential for options such as pregnancy if players show interest in that.
I'm pretty open to a lot of possibilities, it really depends on what the players want. One thing I can guarantee, however, is that there will NOT be any NTR WHATSOEVER. The idea simply doesn't interest me.
There will definitely be lesbian/threesome scenes down the road, but it will probably be a while until the characters reach that point.
Regardless, they will be completely avoidable if you don't want to do them, and they will most likely not affect each woman's individual routes, if you only wish to pursue one.