I don't know what to tell you man, the stuff you point out isn't really something that is bothering me. Sandra and Alice making each other feel good for example doesn't change anything regarding Sandra being exclusive to MC. Same goes for having a threesome with her and alice while she licks Alice. I'm not going to change that because I'm writing this story how I like, if you are too bothered by that then maybe a different game is better for you. Or, even better, you should try making your own game with the stuff only you prefer! :)
as a tl;dr: I'm not going to change anything since it is my game my dude, I read your criticism but the stuff you suggest is not on my mind :).
Also, to reiterate on the Sandra thing: If you are taking the stuff the girls do with each other as "not being exclusive" then you should work on your insecurity. It is a harem where everyone loves each other and the girls only interact on a sexual level when MC is around ( also known as threesomes ).