Only my opinion
This is what I would use Dave. Easier to program and flash as a joystick.
Pro Micro ATmega32U4 5V 16MHz Micro USB Microcontroller Development Board with Arduino Leonardo bootloader (2PCS) : Amazon.ca: Electronics
Uno and Mega a little more tricky to program as a joystick.
I do like the Gikfun Screw Shield Expansion Board thou. Looks pretty useful.