Dedicating a good portion of the development to a niche which disgusts most of the audience. Why does it have to be there? Why? Why not scat, guro, necrophilia, and or pedophilia? Make it entirely optional. It's completely "fine". I just wrote it, so it must be true /s.
Scat sounds nice and also some level of guro. In fact the new game I'm working on will have some golden showers as a feature (which might be optional as well considering the relative notoriety of this fetish). Having said these, there will be no pedophilia at any time. Zombies might be a gray area for necro. As for the futa options as a possibility, it will not involve the main character as he is hetero but futas or gay characters appearing as a part of the story or the game world are there.