I actually prefer an ugly villain in hentai over the sterotypical bland lead whose hair covers their eyes. I just feel like they add so much personality to the hentai.
I can see why some people like it but it can ruin it for me because I don't watch/read hentai to see ugly things. If the art or story is hot enough it might be able to make up for it though.
I hate the bland bowl cut protagonist from almost every anime/manga more than the ugliest of bastards in hentai. Stop pandering to hikkikomori and start coming up with protagonists people can look up to.