I'm eventually open to a streamer upgrade, but I've gone the practical route until I learn a bit more. I've had a Bluesound Node (3rd gen), and both Cambridge's CXN V2 and CXN100. The Node is running wireless in the basement. The other two are wired from the routers. I am unsure which would be replaced in an upgrade gesture, given the capabilities of their respective systems. They seem to be in the "good enough" category for me. For now.
The CXN V2 runs through a separate dac, and is slightly better for it. The CD transport upstairs run through the CXN100 dac. The Bluesound Node is RCA analog out to the preamp.
I am going to muck about with the basement system via some tube rolling, using Cowboy Junkies Songs of the Recollection, using both streamed and CD as sources for comparisons. If my intentions remain organized!