To be fair, my video plex libraries are all nice and sorted well, my plex music library is a mess which I so far found a bit clunky to cleanup. Mainly due to mixed artists albums, which plex tried to organize by artists first.
If someone has a very well-organized music collection, Plex as a music server won't be my first recommendation.
Maybe worth checking out Roon. I am not familiar with it, but some very technical folks seem to like it a lot:
Archimago for example -
http://archimago.blogspot.com/search?q=roon
I won't switch to Roon just for music steaming, simply due I am too cheap to pay $10/month for it since I already paid for a lifetime Plex Pass (at 50% off sale price). Plex also has a mobile app (PlexAmp) that supports both android auto and carplay. It's not perfect, but it works. It also converts audio formats as necessary, I know my passport audio system doesn't support lossless files, but on PlexAmp I can stream lossless files, converted in real-time to supported lossy format by the server - all seamless to me.