I like it! but since its mainly brandable, its pretty hard to give an estimate.
My advice for you to build it out, or wait till the right buyer will drop by.
Not necessarily, development does not have to be the golden way to proceed. If a high end developer decides to buy such as domain the original site will most likely be deleted as the first thing. Especially if we are talking about a standard Wordpress site with 10 generic posts.
Development is not bad, but if the driver is to raise the price significant more than a few posted articles or a handful of forum members is needed. Serious website development is not a single afternoon assignment.
The resources spend making a site might be better spend looking for end users.
Agree that singular version is better, but in this case i don't think that the plural hurts too much in comparison to a lot of other "plural domains" posted here. Especially if used for a forum 'fans' seem natural.