If you have access to all devices, why not just use your own self signed certificates to encrypt everything and require the certificate for all connections?

Sounds like you are describing a VPN. I was using that setup before but small stuff like immich album sharing via a link won’t work properly. Also, having to ensure a vpn is on and connected is a little to much to ask of my partner; they would turn it off and forget about it and then ask why their app wasn’t working :/

Grayjay by FUTO has been working well for me

I currently have a nginx docker container and certbot docker container that I have working but don’t have in production. No extra features, just a barebones reverse proxy with an ssl cert. Knowing that, I read through Caddy’s homepage but since I’ve never put an internet facing service into production, it’s not obvious to me what features I need or what I’m missing out on. Do you mind sharing what the quality of life improvements you benefit from with Caddy are?