You would need to consider how peers can discover each other. Even if routing data can be extracted from the block chain, the protocol requires direct communication between all parties (ie, TCP connections). IP addresses change. One possibility is to require all participants to use Tor and then embed your hidden service key in a transaction. That way you get authentication, encryption and privacy for free. This boils down to using (abusing?) the Tor HSDir servers as a secure rendezvous mechanism. The short key hash (onion address) can be added to the channel transactions using OP_DROP. Note that whilst the Tor protocol is very slow/heavy for connecting, there is a proposed optimization for the case where participants don't actually care about being hidden:
My idea was a separate P2P network, where the cost of the identity and cost of the message transmission could be expressed and verified (either directly by bitcoin payment, or indirectly by burning coins).