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!