If the idea is to deploy boringproxy or other reverse proxy/tunneling software on a vps just for one self-hosted machine, why not just setup an openvpn server on this VPS and redirect all the traffic into it…
We already have a vpn client app . We should consider to rework on easy deployment of vpnserver app.
In fact you need proxying only if you want to split one IPv4 onto 2 or more machines. But if you have a vps with 2 ipv4, you can create a “vpn self-hosting” for 2 machines…
Proxying is harder to implement…