Depends on the game — I don’t really follow harem or incest stuff, so I can’t speak about the models used there. But Medical Special Care, for example, features exactly what you mentioned: three paths — Love Route, NTR, and NTS. You can play as a full-on 'alpha' male MC if that’s your thing, just keep the wife on the faithful/love path while the male MC takes some cheating and netorase options.
The game offers a lot of flexibility, which is why it’s my favorite. And yeah, it’s also a perfect example of what you said — great-looking models (Eva the Wife is the most hottest Milf I ever saw In a game) and solid content.