Hi John,
reading all you have been busy for a while 
You find all my Roon Extensions here rooExtend - Home.
Despite discontinuation there are still Senic Nuimo devices in the 2. market. Me and @Klaus_Engel always post our current findings here: rooNuimo – best Roon controller ever - Audio Gear Talk - Roon Labs Community. In my eyes the Nuimo is still the best choice for Roon control. But it is expensive today as many sellers recognized that a lot of people ask for it now
The Microsoft Dial is cheaper and available but has no display nor such a broad set of capabilities. I personally also like the SpaceMouse as it is rock solid and has a highly reliable wireless connection using its own dongle.
Nuimo and SpaceMouse (both Bluetooth) are mutual exclusive on one Raspberry Pi. All my other Roon Extensions can be run on the same Pi without any interferences.
A nice overview of the complete ecosystem can be found on the support page of my new rooExtend-Box rooExtend-Box: Plug-And-Play for Roon Extensions - Audio Gear Talk - Roon Labs Community
Hope this helps. if you have any further question fell free to ask.
Best DrCWO