But those who only want Father / Daughter route will lose a good part of the game
So, the game is very, very NTR/sharing/swinging oriented, right?
Honest question, why not make totally different routes with totally different content? Why do you decide to make one NTR route and one non-NTR route when, from what you say, I will miss out on much of the game if I choose not to share the daughter? I don't see the point. It would be better to do the whole game NTR/sharing/swinging if I am "penalized" with content for not wanting these routes. If you offer the opportunity to play non-NTR routes, you are heavily "punishing" the players of these routes.
The most logical thing would be for each route to have its content.
-If I choose the NTR route, I will get NTR.
-If I choose the non-NTR route, I will get totally different content. I will get non-NTR content and I can have the same amount of content as the other route.
That's the way I see it.