The fundamental thesis behind noisy sockets is, "What if your network endpoints were processes instead of machines?"
And as you say bypassing the host networking stack actually brings a lot of benefits (eg. avoiding those VPN leak shenanigans), it's actually interesting when you squint enough it begins to even look vaguely something like QUIC (in that you have multiple encapsulated streams/channels/sockets going over UDP with their own congestion control).
Peer discovery and NAT traversal are next on my list. I'm going to implement a kind of userspace lighthouse peer that will advertise peer endpoints to the network. I'm still trying to think about how I will deal with TURN/DERP. I suspect I'll tunnel WireGuard over WebSockets and just have each peer listen on UDP/TCP. Maybe one day that will allow even an in browser peer with WASM (which I'm sure someone will find an interesting use case for).
Also on the list is fine grained authentication/authorization (interestingly netstack has an iptables implementation), some of it will be opensource and some of it will be source available (sorry for the SSO tax).