Basic Digital Audio Setup Advice

Greetings! Looking for some feedback on a wired digital audio setup. My primary goal is to play hi-res (up to 24/192) lossless files bit perfectly in a plug and play fashion.

Here's my current (modest) arrangement, my iMac is too far from the DAC to hard wire, forcing use of Airplay and downsampling to 16-44.1...

2014 iMac w/ external HDD (~4TB of FLAC/ALAC files) > Audirvana 3.5/Roon (both on trial currently, migrating from iTunes/Music) > Airplay (via Airport Express) optical > Cambridge Audio DACMagic Plus > Rega Brio > Q Acoustics 3050i
I'd like to add a server/streamer next to the DAC that I can access remotely to take the iMac out of the chain. Initially was looking at a headless 2012 MacMini >  DAC using Audirvana/Roon but I know not truly dedicated to audio.

When going down the Roon rabbit hole I was intrigued by the Nucleus in place of the Mini. I would likely look to move the file storage to a 2-4 bay NAS accessed by either the Mini or Nucleus.

It feels a bit askew to spend more money on the server/storage than I'm into for the DAC/Receiver/Speakers but the ease and cleanliness of the Nucleus has a lot of appeal.

Are there any simpler/less expensive options I'm overlooking that might help me accomplish my playback goals, keeping in mind my audio component level? I'm not very keen on having to assemble so the NUC/ROCK option isn't something I've considered. I also looked at the Bluesound Node2i but feedback on the OS is poor and sounds like some challenges with being actually Roon Ready.

Thanks much!
As I understand it, a Roon Nuc is a stripped down single purpose PC based Roon Core device... I think its better than your iMac as far as noise (read EMI/RFI) is concerned... However it is still not as quiet as a ROON ENDPOINT might be...

The trick is to run Roon Core on your iMac (Nuc or other general purpose computer) and have an Roon Ready network streamer/player (aka Roon Endpoint) connected directly to your DAC... In my case something like this:
Apple MacBook (Roon Core) -> ethernet/Wifi/LAN/WAN -> Lumin U1 mini (RAAT/Endpoint) -> USB -> Chord Quest -> PreAmp -> Amp -> Speakers...
@travisnordgren - Have Roon Nucleus in my main rig feeding Chord Qutest via Curious USB Cable. Have Melco N1A functioning as a combination NAS and ethernet line purifier with Nucleus tethered via ethernet cable (AQ Cinnamon) to Melco's player port.  Been running this configuration since November when I acquired the Nucleus and have been very happy with it.  Earlier this month replaced Nucleus stock switch mode power supply with 19 volt Sbooster LPS, which also allowed me to use better power cord (Shunyata Venom 3).  This provided immediate benefits, but Sbooster is still breaking in.  As it so happens, the Nucleus replaced a Bluesound Node 2i in my main rig.  The Node 2i is now part of my desktop system, and functions very happily as a Roon endpoint.
" . . . There is so much else going on in a PC. System monitoring and all sorts of stuff that you don’t realize. . ."

This is where Fidelizer and/or Audiophile Optimizer comes in. They shutdown or re-prioritize computer processes specifically for audio playback. The results are a lower noise floor and improved tonality. They can be used separately or together. If together, Fidelizer provides settings for a handshake. Still with anything digital, good LPS’s with good power cords are required to get rid of digitus completely. A PC requires a different kind of LPS than a router/modem. (It’s more than a voltage issue.)
If I continue to run the Roon Core on my iMac but it is connected to the network via WiFi (not Ethernet), will the signal sent to a Roon Ready endpoint be bit perfect? Unclear as to the integrity of the signal being sent to the endpoint over WiFi. The files would be connected to the iMac on an external HDD.
The Roon/Nucleus solution looks appealing; I agree wireless options and headless Mac minis are undependable. One cheap solution: a long toslink cable to your MacBook if it's one that still has the optical out, or to a HMDI splitter if it's a new MacBook without the S/PDIF. Not perfection, but less than $100...