Appreciate all of the replies and information. A bit more context.
My two channel and headphone system consists of the Bartok APEX fed by the Aurender N20 via AES/EBU (which does not carry DSD files, it converts them - USB is required for DSD). Most of the time I listen to local music files stored on a drive in the Aurender. I still buy music, download and move the files to various drives (Aurender, Roon, backups).
I also stream via Qobuz (longtime), Tidal (new’ish) and Apple Music (very new) plus Bandcamp and Hearts of Space. Bandcamp is streamed through an app as is HoS. With the two channel system I tend to stream from Qobuz and Tidal through the Aurender because I’m already in the app. I often forget to stream through Mosaic.
This is my main system and it’s fantastic (Luxman integrated, Harbeth speakers)!
Now to Roon: I had originally fed the Bartok through Roon and the Nucleus+, but the Aurender, purchased mid 2023, was a very clear improvement in SQ. I then relegated Roon to a second headphone system (now sold), but it also served as a source for other devices around the house, as the source for ARC (I could stream my own files) and as a backup of all the audio files.
I have a couple of Apple HomePods around the house and a pair of KEF LSX2 speakers in the living room. I would stream from Roon to them, but naturally that’s not required.
Again, I had been using Roon less and less, since I can stream from several services through several apps and devices. But when the Nucleus+ apparently died I thought Roon might still have use. But now I’m not so sure.
I do have a NAS for photography use / backup and career portfolio backup. Coincidentally, I turned it back on yesterday after 2 years (it was in storage during a home remodel) and thankfully it works fine; updated the OS. I’m not very technically inclined when it comes to NAS and never considered it for music playback.
About those DSD files: I don’t have many, but they do sound good. In my case, I’m not sure I need to optimize for them. If I really wanted to, I could play them natively via USB from the Aurender.
To wrap up: I was frustrated that the Nucleus+ had died (maybe it can be resuscitated) and I defaulted to the path of replacing the Roon Server device and made this post, but after feedback and more thought I don’t know that I need to. I have a fantastic two channel system without it and I can stream to all other devices around the house using apps on hand.
And no, the file management and metadata is less useful to me (I just love the music!), and anyway a lot of the streaming services are fairly robust with metadata and pivoting from one song / artist to another for discovery.
I have a Roon lifetime membership, I can easily go back anytime.
I do appreciate the thoughtful comments and feedback here. Thank you.