Just in case I need to say this, I was generalising, and not at all calling you out on thinking they are equal, or anything like that. I really am surprised at all the hate Sarah gets, as I consider her one of the better-looking girls in the game. I think a lot of it is her character though, and people not separating that out from her looks in these conversations. But again, different people have different tastes as well.
I'm not a Quinn fan in terms of looks (although she has a great body - did I see somewhere that it's Maya's body but with the natural instead of fake tits?) but I would still put her above Mel. Bella... I'm not sure, I'd have to have a proper think about it. They are so different, but Mel and Bella might rank about the same for me because of the things I don't like about them, as opposed to the things I do.