CT- PM me and I will email both you and Matt together. Matt has my email address.
Your goal is to have quality, simplicity, reliability and versatility.
Fiber optic is just an alternative to wired Ethernet. It is much cheaper than moderate priced ethernet cable and it provides galvanic isolation. Like your power lines the Ethernet cable carries other currents that mess up digital electronics, especially the DAC clocks. The switch power supplies are part of this issue.
In your situation, wireless will not have enough range to reliably drop two or more floors. Wireless will limit high resolution files both DSD and PCM. Optical can run adjacent to electrical cable, whereas low voltage cables need to be 18" away, depending on local code. When they cross ideally they would cross at perpendicular angles.
Second option is to have two independent systems: Comcast provides two accounts: two modems and two independent networks. While this may decrease certain noise perse, you would give up versatility and create some redundancy. Although two NAS systems would provide some backup.
To run cable would not be too expensive and you can find someone to do it for you for reasonable price. In your situation, I sense you are running dedicated power. I would run fiber down to your listening room. From there the options are many and easily changed when needed--especially important as digital audio is rapidly evolving.
A newer NAS (not my generation NAS) has the advantage of negating the need of a server or separate CORE processor running ROON. I however do not see a sonic advantage at the moment since your NAS is a large source of electrical pollution. I am also researching HQPlayer and if that program will process files then use UPnP/DNLA type protocol. I am uncertain if a ROON>HQPlayer will process then send by RAAT (Roon Advanced Audio Transport) codec to RAAT capable Ethernet units. My understanding thus far- HQ player will process (by server) and send by USB to a USB dac only. For clarity ROON, RAAT and HQ Player are new to me.
Does the new EMM dac have Ethernet?
I’d rather not distract from the overall thread. I will post any valuable and succinct solutions when appropriate.