I'm not turned on by pure MM, although I can be fine with it when women are involved.
It's funny, while I've enjoyed many stories by famous gay authors over the years, I've always skimmed over the sex scenes, feeling squicked. But after having spent time writing a few, and seeing they're all essentially tab b in slot a variants, they're now much easier to read and I have no problem reading the entire stories through. However, there's a big disconnect between erotic scene written from a male and a female perspective, and that's exaggerated when they're not regularly exposed to the other sex's perspective (i.e. gay author's writing is less affected by female complaints). Then again, for every female turned off by gay erotica, there are others turned on the same way we guys are by lesbian scenes. Which just goes to show, don't be too quick to judge. You never know which of your relatives just haven't come out to you yet!
As far as modifying the codes, we had more extensive codes on SOL before, and they never really worked. The problem isn't the codes, it's with the 'majority opinion rules' philosophy, rather than 'every voice has something to offer' which is more common in literature (assuming you don't talk about the traditional publishers).
As long as you have scoring, you'll have the same imposed-morality by the majority issues, and scoring does help readers select stories, but we need to be aware it also chases different voices away, so we're only hearing a choir of like voices. Often, understanding and recognizing the issue is half the problem--although rectifying the problem takes much longer!