As you say, I won't engage in polygamy. I have enough with only one wife ordering me around
I played AVNs as the good guy. If I was not forced into it by the dev to continue the story, I preferred to not rape, molest in their sleep, or make anyone unhappy. At least in my first playthrough (what I considered canon for that AVN).
I see (A)VNs as an advanced version of a collection of books that were published in Spain when I was a teenager called "Elige tu propia aventura" (Choose your own adventure). You were reading and got to a point where you got (f.ex):
* If you go into the forest go to page 65
* If you go to the beach go to page 134
A book like those had like 5-10 different endings (and the good ones even had completely different stories) and I even did a kind of walkthrough or map with all the options.
When I discovered AVNs they reminded me of those books, and I wanted to read all the things the writer had thought for every girl, so my first playthrough always is a catch'em all. That's why I don't like the games where you can start a relationship with X girls but in the end, you should only choose one. I feel like I've forced the MC to cheat on his "true love" all the playthrough.
But that is only a personal opinion.