For most of my music listening needs, I self-host SwingMusic and keep it pinned in Firefox. Occasionally I'll open the music files directly with MPV or VLC.

The automatic lyrics fetching and playback sync in SwingMusic is pretty nice. My only complaint is that it doesn't let me do full-collection shuffle. Ideally it would also allow me to do something like "full collection shuffle but only of songs that I have never heard". Sometimes I'll pick up an album because it seems interesting but things happen and I forget that I added it and it might languish without listening to it for months or years.

I'm waiting a bit for this to mature before I try it out, but I've seen that there's a few ongoing projects to analyze your full music collection to do feature extraction and generate smart playlists using AI tools. I'm not sure if it'll pan out but it seems like a fun tool for exploring large music collections and possibly making unexpected connections.