For the record, I'm in favor of having rating-specific 'popular' pages. This is just more of an idea to even things out with the vote system overall. Let's see if I can remember what I was going for here...
From what I gather, the majority of users that only come here for porn don't pay much attention to the rest of the site. They don't really upvote images often, they just add them to their favorites so they can fap later. This is evident in the large number of high-rated pictures that have almost the exact same number of faves as their scores. By removing vote-by-fav, all of those guys that don't actually vote but end up contributing to the score via favoriting will be removed from the equation.
In theory, this will help even out scoring because it'll lower the average score every picture gets to a more even level. Not exactly even, mind you, but you can see what I'm getting at. Let's say the average explicit pic gets 70% of it's upvotes from favorites. Questionable 50%, Safe 10%. (This is based on just what I've seen, of course) Remove that portion of votes and the average scores should fall closer together, lessening the dominance porn has over non-porn images and giving non-porn a better shot at getting the recognition it deserves in terms of quality.
That's just me, though, wanted to throw it out there. Do whatever you think will work.