Why not sell 75% ownership and stay on to assist with the continued development and growth of the site? That way you are still invested and you reduced your risk in a reasonably fair way. For a small site with limited revenues, valuation is somewhat subjective as you are projecting forward with many unknowns.
25% ownership doesnt appeal to me as much since I'd lose control over the direction and in that sense, I'd rather sell than work on it for someone else.
