I just stumbled across https://tools.ietf.org/html/draft-droms-6lo-ethertype-request-00 and thought that transmitting 6lo directly over Ethernet (as opposed to ZEP encapsulation) might indeed be interesting to support for debugging. Now that we support Ethernet devices, this should actually be very easy to implement, I guess.