I still believe the easiest answer is ranking the vote...choose ten images and rank them 1 to 10 so that if you are asked to vote for a friend,you can do so and the other people in the contest still have a fair chance of winning.If the ranking is somehow secret,your friend would know you voted for them but not what position lol.Trolls would find a way around any rotation system by just showing their friends the image they made...send it by email to them.
The same rings equally true of the top 100 images,some images have many viewings either because people troll for comments or simply make comments on a lot of images with the result being that these people return the favor (the latter not being intentional and thus,not trolling).Once you've established a fan base and are on a large number of favorites lists,then you can guarantee a certain number of comments given to you as people who don't even visit rosity still get alerts to your new images and will visit to see what you've done and comment.So even those deserving to be in the top 100 are stained by those who are there because of the system...anyone who judges their talent or ability by it are thusly getting screwed rofl.Now that there's a limit of one image uploaded a day,we'll see if more people can break into the top 100 as it does make it easier to view more artists and comment when you surf the gallerys;)

As for nudity,just hit the nudity box in your profile and those will be screened out right?The only suggestion I would make is that in the case with minors,this option be automatic...if they lie and say they're adults,then its a matter for their guardians to handle and not rositys fault if they take every measure to prevent young people or individuals morally opposed to nudity from viewing it.

If the end goal of learning is genius...why are most geniuses failures at learning?