Money is probably the main one, a lot of devs probably struggle to monetize these games enough as is without it. Voices can also be distracting and the way most of these NSFW games are developed releasing patch by patch would mean having to consistently get the VA's back in for lines which...
Not sure if they count as 'monster' girls exactly but for alt fictional race of character I really like Au Ra in FFXIV. Harpies are also up there, pretty cool and a bit more rare to see than the usual catgirls/bunnygirls (although I'm generally a fan of most non-insect monster girls).
Some reasons for me have been that it doesn't have enough attractive girls in it, the game runs like utter shit, gives windows defender warnings and comments in game thread also confirm something is sus, unstable beta patch that will get a stable patch soon, art is bad, too much filler...
Think the largest for an H game I've played so far has been around 13gb or so. For normal games the most I've used for a single game was probably around 130 or so for certain mmos.
RPG most likely just because it's a very broad umbrella category that can include tons of different types of games from series that I already like to play (stuff including Final Fantasy, OSRS, Divinity, Disco Elysium, Persona, etc). Also a lot of them are pretty long so probably pretty easy to...
I like most genres but roguelites lately have been a favorite of mine. Big fan Dead Cells, Hades 2, and Blue Prince to name a few I've played more recently.
Had a pretty similar intro to NSFW games. Initial experiences way back were adult flash games, played those a bit and then stopped playing any nsfw games for many years. Eventually was made aware that there were a bunch of more fleshed out NSFW games and was put on to Harem Hotel by a friend and...
I like them although I don't think I have played much of them lately. Aurelia is probably the main one that sticks out that I played a ways back and it was really good