I've looked now... We have a similar design regarding the leadership roles, with the difference that they support multiple "leaders". However, they use a full-mesh which means sending a message to each user separately. Kiyeovo has "anonymous" mode which routes traffic through Tor. That means that even offline messages that get saved to DHT get routed through Tor. They are already slow as it is when sending 1, now imagine sending 9... Thanks for the suggestion though!