My existing solution involves a Squeezebox Transporter  connected to a QNAP TurboStation 669 Pro  which in turn runs SSOTS  and the PERL source of Squeezecenter .
It's a really nice solution, allowing me to remotely access and play my music from anywhere in the world.
In fact, I've had what I consider to be a personal version of Spotify for the best part of a decade, whilst at the same time enjoying a superlative system at home.
I do have concerns about what will happen now that Logitech has abandoned the range. At the moment everything is working fine.
A remote failed on me a while ago (my own fault) but I was able to use Net::UDAP  to work around it and an Android app on the Nexus 7 to act as a convenient remote.
But... what happens when the QNAP requires an update that shifts the version of PERL? What happens when the libraries for Squeezecenter are no longer supported and later versions don't work with Squeezecenter?
It's all fine saying that we could just use a hardware DAC and wireless streaming. But that doesn't give remote access, an indexed and searchable library, local remotes, etc... and suddenly you need to solve all of these things from scratch again whilst still keeping yourself out of walled gardens.
As for other solutions, I have 91,000 FLAC files. Some of which are 24bit (rips of the vinyl I own). I also use MusicIP to create dynamic mixes of music along a theme... like Apple Genius stuff but far better and more interesting to listen to.
I've always felt that the problem Squeezebox had was that the quality was too high, it worked too well. In over a decade, the only thing that has failed has been the screen on the remote, and that was my own fault for kicking it across the room (accidentally I might add).
How do you make a sustainable revenue stream when your key customers never need to buy from you again?
I'll be watching music/audio/tech forums keenly for a similarly capable system to emerge.