I love the idea and execution. There are some obvious things that will require improvements like more sex animations variety, more characters and clothing variety etc, but dwelling on that is a bit redundant.
What I'd suggest for a better replayability imho is a mechanism in which girls actually differ in behaviour - currently one can conquer all of them with just a bit of mashing of every option persistently. I think it would be cool if some of the dialogue options would never work on a specific type of character or it would require a certain order of raising their statistics - I'd expect most tsunderes (but not all of them) to not get all hot in their pants until their obedience is raised higher. I'd also expect shy variant to maybe have a higher chance of getting hornier the more attention/flirting they get, but any firmness could probably not work on them most of the time. There's also an interesting mechanic of types transformation like in the "Island Deity" game, where a type can transform into certain further types - this could depend on the order or raising stats salted with some randomness per each girl - if that makes some girls unobtainable or unconquerable, but a good worker, that's also a certain mechanic that could spice things up and could mask any balancing issues. For example earlier mentioned shy girl with a little bit of luck could be transformed into a sex-crazed femcel when her obedience is raised enough (a chance of that should probably be on the lower side) or her stats could result in a branching out into a shrinking violet that requires absolute pampering to achieve any sort of progress.