I use Funkwhale, which I have liked, but my use case is just streaming music through my laptop and listening with headphones. I don’t think there is a client available that will run on your Autonomic streamer.
Funkwhale does have a subsonic API, so you could use a subsonic client, but you mentioned that didn’t quite work before. (Is that what you mean by __sonic? I haven’t actually heard that term.)
Funkwhale is nice, but I think for most people it doesn’t (yet) offer any useful features beyond what Navidrome has, and probably even lacks a few things that Navidrome has. Funkwhale’s main appeal is that you can follow someone’s music library via the fediverse, although there hasn’t really been a lot of use for that so far. Version 2 is coming soon, though, and adds a whole bunch of new fediverse features.
Sometimes I hear about other people’s storage setups and I think, “that is overkill, no one really needs that.” According to this thread, I am quite mistaken about that. 😳
I have 2,057 songs, taking up a measly 51 GB, on a Funkwhale server. No movies or TV shows.
That should get a little larger soon. I have about 100 vinyl records that I want to make digital rips of.