Navidrome and it’s smart playlists is incredible. I’ve heard of Gonic and Jellyfin as other options. I think you can share a music link with Navidrome but I’m not entirely sure, I haven’t looked at it in a long time.
Yes and yes. I do actually use a bunch of stuff but a lot of it is for experimenting.
I regularly use Jellyfin, Vaultwarden, PiHole, Nginx, among a few others but for experimenting, I recently set up a container will Mullvad vpn so I can use that vpn networking for my qbittorent container.