It's basically figured out. I just need to document!
I do not understand at this point whether a standalone video card will give you anything more than the onboard HDMI output. I need to do some more tests.
Also I have not compared the Sotm USB card to the USB on the mobo. Another thing to try out. Have you tried it?
I am using the older SotM card in the CAPS2.0. I never compared to mobo USB, but this SotM card is an article of faith among the true believers, so for a few hundred bucks I'll drink the cool-aid.
I would be surprised if a dedicated HDMI card would not improve video quality.
I am still leaning towards a two box solution. Gives me more flexibilty and potentially better SQ on 2 channel, and better video with the dedicated HDMI card on MCH. The price of redundant components is in the $1o00 range, which is less than the price of a Shunyata power cable. Also would not have to figure out the JRiver zones setting and switching between USB and AES/EBU output in JRiver.