best network switch configuration for audio

Yes, it is 1's and 0's but they have to be converted at exact time intervals to avoid additional "products" that result in overall noise.  In your case Ethernet network transfers data and not music.  Music is created when timing (clock) for this data is added in your DAC.  You can still affect purity of internal timinig/clock by injecting noise into DAC.  Because of that I would use dedicated shielded Ethernet cable where sound is the most important to you.  I don't have actual experience with NAS, Roon or Tidal so I can speak only speculate.

Thanks kijanki!
"In your case Ethernet network transfers data and not music." Quite right. What I am concerned about is the data that contains the 2 channel music info as opposed to the data that carries all the other info going over the network.    
 "I would use dedicated shielded Ethernet cable" Roger that also. All "horizontal" cable will be Blue Jeans CAT 6 (or 6a) and kept away from AC circuits. That will help with RF (don't want my ethernet cables acting as an antenna).
I mainly was interested in insight on 2 other concerns:
1)The effect on the system and on streamed 2 channel SQ with multiple long ethernet runs vs fewer long runs with switches and patch cords at points of use.
2)any advantages, any techniques, for isolating music data stream from other data streams, especially those likely to have "noise" from power supplies

Your design seems very sound. In particular, I applaud your use of a POE-enabled switch and wireless access points; I truly wish more people would understand the substantial benefits from having a solid wired ethernet infrastructure that also supports commercial-grade WiFi.

I recommend one ethernet jack per audio location (or potential audio location).  For a 2-channel system, typically the only thing that would require an ethernet jack is a DAC or some sort of audio data transport device (audio streamer) that would connect to a DAC.

For a home theater, get a small switch (I use HP's commercial-grade 8-port gigabit ethernet switches for this) and use this to attach all ethernet-enabled devices (Blu-Ray players, Roku/Apple TV/Amazon Fire TV/etc, audio streamers, modern HT receivers, etc) to that ethernet jack.  There is more than enough bandwidth in even 1 GbE (which cat6 cabling can do easily)  Typically, you're only going to be streaming music or video to one device within that system, anyway; the rest will effectively be on standby.

I also suggest ethernet jacks to every television location, as most TV's made in the past few years are network-enabled.

Ultimately the limitations in your streaming likely lie in your Internet connection.  If you're using a local server, and it's on some very strong hardware, consider link aggregation to connect it to the switch, but this is very likely just overkill.  (I did it because my server and main switch are located together, and I wanted to learn how to use it.)

If you use Cat 6A, you'll preserve the ability to go to 10 GbE and 40 GbE in the future, but it might be difficult to find people who are used to working with cat 6A.  Realistically many cat 6 runs can do 10 GbE, although possibly not if you're pushing the 100 m max guaranteed ethernet cable length.  (It will depend on the capacitance and near-end crosstalk characteristics of the cable.)  But the 10 GbE and 40 GbE hardware is going to cost a pretty penny, and the 1 GbE is enough to handle multiple video streams.  (I stress-tested my system by streaming video to all 3 TV's and 2 wireless laptops at the same time, and my 1 GbE network was more than able to handle this.)  Streaming audio and video allows you to function relatively close to the maximum capabilities of your network, as there are relatively few packet collisions that can really start to slow networks down.

Congratulations on doing your homework with regards to computer networking, and rest assured that one network jack per audio location (with a small switch there if needed) is perfectly adequate.

Michael

The biggest issue IMHO are not the switches and data but the wall warts and the noise they might inject into the power line.

Switches at the rooms are extremely convenient, and often necessary. :-) I have 4 devices in close proximity that need Ethernet access. TV, DVD, Chromecast plus my music server.  Wifi is severely congested here so wireless streaming is unreliable.

I would use local switches when necessary, but try to isolate the wall warts by putting them "outside" any power conditioning.