Just to chime in myself after dropping a vote, mostly because its an interesting line of thought.
Straight male (And though not explicit in your question, almost excuslively in a dom position), I've come to basically play exclusively female protag's in games like these, a male protag is going to need an extremely compelling part to garner any interest for me (Exceptional art, steller reviews of story, which almost never happens, an extremely fun gameplay loop, with things that super appeal to me like Prison Battleship).
Like some other posts here, I'm not playing these games to self insert as the protag (or the villian). But I find the styles of stories which can be told from a female perspective which these types of games work well in much better than a males. Almost all male protag's by nature have to be giant assholes and the entire game is centered around a pointless effort to rape, blackmail, etc.
And a game like that could be fine. But that's it. -A- game. But its sorta hard to innovate on that concept. I recently found a male protag game I sorta liked, as it did manage to veer off that a touch, where you played as a dragon, doing the whole capture the princess thing with some dragon form fun going on (rather than "Oh hey I'm a dragon, but for sex, here's a human form). Which gave some extra motivation and what not (though it was still really under developed, low in art, and what was there looked like it was from disparate artists taken from the net).
Female centric ones I feel have a far greater reach, weather focusing on telling the story of shameless sluts, a chaste knight trying to stay that way, temptation, assault, rape, and a long list of stuff, as well as there's a broader range of pairs that appeal to me (FxF, gang-bangs work out a bit better than FF or MM bangs, in my eyes), non-human partners. Discounting MxM as its simply not something that appeals to me (So I can't really comment well on implimentation in H-Games).
The arcs work out better while allowing sex to happen along the way, and being more interesting. In addition, as a player (for games with real mechanics) I enjoy pushing against the system (i.e winning). But this feels off with a lot of Male Protag games, and most of them just don't have this (I'd guess as a lot of them prefer to rape via blackmail, rather than getting a Guro or Ryona tag involved with a beat'em up approach). While Female protag games very frequently feature some sort of combat mechanic (even if just a stock standard RPGM set up tuned WAY too low difficulty).