Simple:Press was mentioned in the following article:
12 Best WordPress Forum Plugin Options for Community Building
May 2, 2016
Posted on wpkube.com.
The plugin is completely free, and the company has a nice forum of their own to guide you through the process of setting it up and managing it in the future.
You can upload and pull in Gravatars for all your users, rank people with certain badges, moderate each post and use shortcodes to make your moderation process a little easier.