Hello Barry, welcome to the forum.
There are numerous ways to setup and the best depends on the individual. You will probably get several different answers to your question.
Some questions for you. What does your internal network consist of. Wireless, Ethernet or a combination?
The Nucleus should be wired to the router. Wireless works depending on the strength of the router but would encounter problems at various times. Endpoints can be wired or wireless but wired is the most reliable, at least for me.
I would have the Nucleus wired to the router with your music library on a SSD drive internal to the Nucleus and use the NAS for backups. From there its hard for me to say because I’m not familiar with the capabilities of the devices you mentioned.
I have my NUC/ROCK in a media closet next to my network and surround system components with HDMI from NUC to Receiver, USB from NUC to OPPO 205 DAC, Ethernet to PC/DAC in the bedroom and Ethernet to a Roon Ready speaker system in the kitchen.
That works best for me, in my home, with whole house music but would not be best for everyone else.