I think the polyamory dilema can be somewhat addressed by introducing a compatibility mechanic between the girls , for example Jean might be okay with the idea of sharing her guy with someone like Kitty , Rogue and Laura but might be opposed to the idea of Null getting down and dirty with someone like Storm or Emma Frost down the line , the seeds are already there for something like this as she voiced her dislike of it already
If the devs choose to do so they can certainly expand on this as it will not only bring about more varied playthroughs with a different combination of girls that the players can romance on each playthough but also remove the whole porn logic of all for me none for thee , this should make choosing the girls you decide to go for more meaningful
At present the whole friend mechanic kinda makes sense but mostly so with Laura and Rogue but just because you are friends doesn't mean you are willing to share someone you see as more than a friend , this is just my little take on the whole thing
Null does have the power to stop his ejaculation anytime he wants so having like 15 girls all at the same time would not seem out of the realm of possibility for someone like him so yeaah..