I've been using Navidrome for a while and love it (long enough to have written an iOS + macOS client). I mount my music from a B2 bucket and use a shell script to sync additions to it. AudioMuse-AI does a great job generating playlists and populating similar artists. There are lyrics plugins, an Apple Music plugin that can populate metadata and on and on. It's a great system and free from the catalogue rot and slop that's been eroding the benefits of streaming for a while now.