Does anyone have recommendations for good community management platforms?

Site URL: https://www.nafc.org

I currently use Ninjapost for our community forum, which has been nice, but am wondering what other platforms people use for a community discussion board/message boards. We don't need anything really fancy, but would like a way to moderate users and posts, allow users to flag posts that seem inappropriate, and potentially add a paid member section (in addition to the free section we allow for most folks).  Anyone using something they love or would recommend?  

Hi,
If you haven't received an answer yet, you can post on some FB groups
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