I'm looking into a slightly less retro take on this, with the files stored on my phone and played via bluetooth.

Is anyone aware of any geeky workflows for this, e.g. having a giant collection on a server and regularly updating the local selection. A simple player app etc. A service independent way to store favourite tracks and playlists etc.

Or have streaming services stolen all tha air from this sector?

The aggressivness of Apple Music hints that those services will start getting annoying.