Personally, I need for a story to have dialog options for it to be 'very good'. Kinetic novels are fine, but at the same time, If I wanted that, I would just read a comic or a book. If I am playing a game, I want some sort of engagement and for that engagement to at the very least give an illusion that I am affecting the outcome of the story. And it isn't a requirement, but does help boost my perception of the game when its a little more sandboxes and has a world that we can move around in with different rooms and environments as opposed to just railroading you through different story beats via narration.
#1 thing for any R18 game: support play with one hand. Preferably with alternative arrow key layout. Too many devs just assume everyone uses wasd.
Another thing is, regardless of your choice of genre, if you are making a fap game just make a fap game, don't include a history lesson. If you are making a game with a meaningful story, then good luck.
Third thing would be to stick to your vision and not let community opinion and censorship twist it into something unrecognizable.
The kinks, because you can have the best looking game with the best story and characters, and yet the MC is going around and shiting in other people's mouths , so the kinks are the most important thing in my opinion.
It should stand out. Either by quality of content or by daring to do things other devs don't.
If there is art it should at least have some quality to it. Don't make art that makes dicks wilt. If you are shit at it text will do just fine.
Should not be afraid of offending people. Interesting topics are often polarizing. If you try to make everyone happy it will only end up being mediocre in every way.
Not introducing censorship or other bullshit in an attempt to scam your way into steam or other mainstream platforms. If a game can squeeze its way into steam it just means its been crippled and is boring.