Sonic differences between servers

on your criteria you might want to look at an OpticalRendu with fibreoptics connection to your router. 

@OP, 
After having a Bluesound system, I recently moved to Innuos.
That required a new app to stream music. I bought Squeeze Control, but found Roon to be superior. -Especially in the user interface.- I don't think you'll find a better one.
Bob

Ironlung

At the time, I was running Roon Core on an optimized Mac mini and using the Auralic Aries G2 streamer. I had (at the time) both Tidal and Qobuz though I’ve since dropped Tidal as Qobuz sounds better and their library is satisfactory.  

I honestly don’t recall if I compared files off of my Mac Mini hard drive over Roon and Lightning DS (“LDS”), but music streamed from Qobuz sounded significantly better on LDS than via Roon.

I haven’t an explanation, but have theorized that LDS manages the substantial buffer in the Auralic better than does Roon.  In usage, I don’t really care why as even though Roon as a library management system is better, LDS is plenty good enough.

  

Roon isn‘t anywhere near the sound quality of the Squeeebox server InnuOS uses: all the plug-ins are detrimental to SQ. This has been covered on quite a few threads on this forum. And I am talking of InnuOS servers running Roon, never mind the Roon Nucleus which is barely better than a PC.

OP

I would look at Melco.  Half size components, excellent player/server, and a Roon endpoint