@kumankahn. But, honestly, I just want to listen to music that sounds great and is easily located and selected.
Looks like you have to main goals for your music: (1) sounds great and (2) is easily located and selected.
(1) Seems like a hardware choice. Since your RC-1590 has a DAC, I'd look for a pure media server. Take a look at the Innuos ZENmini
http://www.innuos.com/en/catalog/go/zenmini-mk3-1tb-hdd.
They are simple to setup and configure; are CD rippers; and come pre-loaded with Roon. They cost more than the Bluesound Vault 2. I use a Zenith MKII. The SQ is outstanding. Check out the online reviews.
For connectivity, the ZENmini has two Ethernet ports or a USB port. In your case, you would connect your LAN cable to the ZENmini "LAN" port, and then the ZENmini "Streamer" port to you RC-1590 "Ethernet" port or the ZENmini "USB" port to you RC-1590 "USB" port.
(2) Seems like software choices. I'd give Roon a try. If that doesn't work, there are a lot of other choices.