@Dunedan I'm thinking of adding a single-user lobby mode: one-time hosting using a single user account.
Initiator connects via trusted address, lobby listing happens only when initiator is connected, nothing is ever sent to MUC chat. Rated game report can also be sent on behalf of the initiator.
I know this a a grey area, but I'm open to suggestions, how to make it not disruptive to the community and still useful for players.