I don't think it will add value more blacklists equals more people leaving I did think it was a good idea at first but people will just abuse it with friends by ganging up with friends and getting them all to blacklist people they don't like and in turn make other people blacklist them to there is always good and bad in most things but more bad will come out i mean with the current blacklists so many people wrongfully blacklisted and left the Blockchain for good