Depth. Having 100 characters in the cast means none of them gets proper development. Having a smaller cast allows deeper immersion in their personality and content. Same goes for fetishes: if you have a game that promises to cover every fetish in existence, you can bet your ass you are getting...
Why on earth would futa be "the most incredibly fucked up thing ever"? Hermaphrodites exist in nature since times immemorial. Why would primates be any different in an alternate evolutionary universe?
The main point of adding them is to brag "This game has animations" and rake a few more subscribers. People should be more discerning with the quality of the products they sponsor and hold the devs accountable for their promises. Unrelated, same thing happens with every game that advertises...
Good story, attractive art style and kinks, kinks being the strongest point. I'd rather play a mid-looking game that includes my fetishes than a photorealistic vanilla game.
Depending on the nature of the mini-games. If they are annoying or time consuming, I'll find a way to cheat them. If they are well made, no issue whatsoever. Some minigames even offer content on their own (remember Gwent?)
Management games are naturally grindy, but they are also some of the best adult GAMES. You cannot really consider a VN where you press skip until the next binary choice comes on screen a game.