Hi Rob,
You might have better luck selling if you exit completely. I know I’ve been in some tricky ownership situations before. If you sell the site and maintain 25% ownership, then whoever buys it does 100% of the development work, right? and they also have to do the monthly accounting or whatever, right? it’s a good deal for you then, but the buyer will find themselves tied to you a little bit.
So I’m just saying bigger affiliates would be more interested in picking up your property with no strings attached.
Although I personally think you might get more out of your site by developing it at leisure and keeping it yourself. I bet it will do better and better as time goes by.
Nice site!