Plus tor hidden services -or whatever the current nomenclature is- offer a fairly robust and painless story for authentication in this "sorta VPN" scenario. Generate a couple extra keys and invite a friend and his bots.
I do the client auth feature. The chances of someone stumbling across my hidden service is pretty low I think, but it’s not zero. With auth set up I don’t think a Tor client can even get the Id of the rendezvous server without having the correct key.