A slightly different approach might be to try WP Idea Stream & BP Idea Stream ( on github.com/imath/wp-idea-stream & github.com/imath/bp-idea-stream )
They allow front-end posting to a type of custom taxonomy – “Ideas”
These are plugins written by the current lead developer of BuddyPress.
Though not recently updated they, like Social Articles, appear to work perfectly.
IMHO they are pretty awesome – yet very simple.
They include the ability to assign categories & tags but also to ADD new tags.
Included also are specific related widgets and an in-built rating system.
They also work perfectly with this developers recently updated media management plugin Mediatheque at github.com/imath/mediatheque.
One big advantage is the ability to seamlessly integrate Ideas into BuddyPress Groups which for many is one of the defining features of BuddyPress.
@valuser thanks, I will also try them