I have 2 niche fetish AVS sites. The content is hard to find for both of them. None of it is exclusive. They do ok, I keep trying to push more traffic to them. I've had one up for 3 months, and have members who have been there since the beginning.
But they are small niche fetish sites. One I don't know of a single pay site in that niche. The other, I only know of one, so it isn't like I have a lot of competition with paysites.
Eventually, I'd like to convert them to paysites and get exclusive content shot for it, in addition to the bought content I have.
Narrow your niche. If you could find something like I did that, ok maybe the content HAS been seen before, but it hasn't been massed and grouped where all of it is in the same fetish, that could work.
And I agree with Paul, keep the navigation simple and easy to find what they are looking for!