I've verified that with the pending wtxid tx negotiation and mempool message, we finally have 100% coverage of network protocol from getheaders (31800) through wtxidrelay (70016), with the exception of bip37 (bloom filters), which is deprecated (and we implement the not supported signaling). The other much older deprecated messages are either implemented and disabled (reject, alert) or obsolete and ancient (checkorder, reply, submitorder). That's all there is apart from going back down level to blocks first, though I've disabled that code.