As far as I know, since the game is still in an early phase, if you have sharing and NTR off, you as the MC have to lift all weight to change behaviour and clothing style over the run of the game. If you have one or both on, influence becomes a factor, esp. with both on. This can be good and/or bad, depending on what you want.
But there is another point. If you leave both sharing and NTR on, influence becomes a factor, but you also have the choice of a general outlook on life and politics. One choice gives you a serious stat boost early on, making it a lot easier to counter your rivals and get the influence you want to have and shield off those you don´t. The other choice gives the snoop ability, which is definitely more useful for those aiming for sharing. And for those wanting NTR if coupled with some choices, since as I wrote before sharing is less harsh and much more consensual than fullblown NTR.