Hello again Sem. I wanted to update you and THANK YOU again for the original post on this project. I decided to take the direction of your above comment about using 2 USB ports as an option.
I used 2 Arduino Micros' and 4 encoders to get the 3 needed rotational axes for HDG, CRS and ALT plus an extra I will use for another function; plus 4 buttons. I used your original 2 axes sketch and changed the joystick ID like you said.
This works flawlessly. This sure makes IFR flying and intercepting radials much more realistic than it is using a mouse or dedicated single button to turn these dials.
Sem, Your a HERO in my book! Thank you again for posting this project.