Great question! It's awesome that you already have some "customers" and validation on the type of content that will work well.

My advice is to form a Customer Advisory Board with a few of the members. Do some exploratory research with them to find out how they'd like to see the community evolve. Do they have unmet needs that you could be serving?

I put this in another question but "Find products for your customers, not customers for your product." (Seth Godin)

There are so many options available to you! You could keep the community as-is, on Facebook, and start recruiting new members for a monthly fee. You could also move to an email list & charge partners for sponsored-content. And, you can also build out the website and try to push traffic to the site, making money off of Ad-Words.

It really depends on what you feel comfortable doing AND what your customers want from you, how you can continue to build value for them.

My philosophy is that you can take the guesswork out of building a business by doing research & asking your customers.