As for the gameplay aspect, I think that a good game should be really challenging, the whole thing that makes games fun in the vast majority of cases is that they provide challenges. Just try different strategies and you will succeed.
As for the porn/sexy stuff aspect, I agree the game is pretty bare in that department, the gameplay is super fun and addicting, but I really hope the dev expands at least somewhat on the sex related stuff before declaring the game done and moving on to something else. I think the game is good, gameplay is amazing, but it needs at least just a little more sex content to push it over the edge to being up there with the absolute best top tier H-games out there.