Web-Of-Trust
I propose to start a creation of a Web-of-Trust. Every user can request a trust state to the Web-of-Trust rating members. The rating members will be community members with a high level of trust, a lot of experiences in different FairCoin/FairCoop projects, maybe a minimum age of FairCoop membership, ... The rating members will receive a list of requests of new users ( data get by a simple form to explain their situation and which fair projects involved ( also outside of FairCoop ) )
Also if users misusage our services then the rating members can rate the user down.
To decentralize it the number of rating members should be high and in every local node should be minimum one rating member.
The rating itself can't be done only by one rating member but need a check/confirmation by others.
Longterm I could imagine to create a full decentralized Web-of-Trust but for the start we need to get experiences first and see how spammers will react.