Like you, I have a large collection of files. I keep them on my PC. With Minimserver on the PC and a fine app BubbleUPnp on an Android tablet, I choose a file to play, it goes over a wifi network to a receiving box (Denon HEOS2) and then to a DAC (it could go by Ethernet cable instead). The analog output from the DAC goes into the audio system proper.
Note that this setup does not depend on Windows audio functions, which are rated substandard.
Almost surely, your NAS could fit easily into this scheme instead of storing files on the PC hard drive or SSD.
As more or less noted above, an app like BubbleNPnP on a tablet has a much larger screen than your DACMagic. It can all the details of the file and album art.