Could you make an option that enables the user to automatically (without clicking) take control of the remote device? Also, so that he can automatically exit the control mode when the cursor is at the edge of the screen from which the input was made.
I use Spacedeck to control my laptop from a computer, and the extra clicks and keyboard shortcuts annoy me a little.
If I could enter the laptop control mode by entering the Spacedeck Viewer window, and exit it by reaching the edge of the screen with the cursor on the laptop, it would be more convenient. This would actually be combining two devices to control from one, and the transition between them was like a cursor transition between two monitors on the same computer.