I ended up settling on Roon https://roonlabs.com/ (It's paid, not Open Source) after having tried Ampache, Subsonic, and many, many others. The UIs on most of the open source music apps are terrible, and they don't do well with a large music library and were always crashing on me. Roon's apps feel a lot more like Spotify and it can do multi-room lossless audio across many devices.