Alright, the R-26 works perfectly with the patch too! Through its built-in controls, first I configured the MENU->AUDIO I/F SETUP->SAMPLE RATE to "96.0 kHz."
Then, I connected it through USB and used this to capture & playback: arecord -D hw:R26AUDIO -f S32_LE -r 96000 -c 2 ./file.wav aplay -D hw:R26AUDIO -f S32_LE -r 96000 -c 2 ./file.wav
Then, in the "AUDIO I/F" tab on its main screen, I enabled "LOOP BACK" & "DIRECT MONITOR" & was able to begin a new composite recording, voicing-over what I'd recorded earlier, by playing it back while interjecting.
Fun, fun, fun, and sounding excellent!
While I don't want this patch ignored, perhaps wait a bit just for now, as tonight I'll be fact-checking it against the USB IDs I've realized can be found in a collection of them: http://www.linux-usb.org/usb.ids. When done, I'll submit the finalized patch.
Thanks & Happy Hacking!,
Lucas