I would love to use Universal Control on two devices with one in "Sends" view and the other in "Fat channel" view.
The ability to sync select between devices is already incorporated, being able to touch a channel in the sends view and have the Fat Channel view hop over to the selected channel would give some more screen space on multiple small devices and create the ultimate small tour setup combined with the studiolive rack mixers (picture with a laptop instead of a second tablet to clarify the idea)