Performance is good and streaming works well. Not a fan of the webinterface personally but there are client programs available for all platforms since navidrome exposes the subsonic api.
Personally I use sonix on windows and linux as well as symfonium (paid but really great app) on android.
The only thing I am missing from it is better user management so that I can restrict specific users from accessing parts of my library.
Regarding access from outside my network I specifically wanted to avoid needing to be connected to a VPN so that's why I use a cloudflare tunnel. Since my upload rate is not very good I have a Pi-Hole DNS server at home so that queries to my domain while in the home network don't need to leave my network.
I wanted to write a minecraft mod. I have never written a minecraft mod but I got interested in actually learning to program after I realized I had no idea what I was doing. Also english and computer science where the only 2 subjects in school I was pretty good at