first thing I would do is make it a hotboat site....as in .. the main forum would be just about boats, like the political section, boat only threads..
next the sand bar would be a separate section..social type form section...next I would have plenty of swag type item's, as I feel that t's and hats would carry the cost of the forum...then I would have an advertisers section, and make it affordable..and have main sections like, boat, offroad, remodel, pro services,...offer a get you in type deal with free advertising for a period...there's plenty of traffic at this site, so there is a value there...