Some suggestions for communities section

Hopefully useful; if you think the pointer the the site/working paper that Ewa and I have been working on is not workshop related enough, no worries to remove it, the cite to Millington is still relevant.

note: this pull request should be independent of my author details one.  If it isn't or I screwed up the branching etc, let me know and I'll re-clone from scratch and get em separate.