Recently set up something similar. DNS entry that resolves to a local ip, swag + letsencrypt reverse proxying to Nextcloud, all setup as containers and accessible anywhere over WireGuard. I'm pretty happy with it.
It does seem like an interesting and useful project, though there are also other more popular alternatives like Caddy: https://caddyserver.com/ (even though their V2 not being backwards compatible was a tad annoying)
Apart from that, just wanted to say that WireGuard is absolutely lovely! Pretty simple to set up, works well and uses way less resources than something like OpenVPN.
