Here's my design for a stick protector for the DJI Spark controller. While it also works on other DJI controllers (tried it on the Mavic Pro's) this is designed for the location of the buttons and the absence of a screen.

The print in the picture is with PLA at 0.1, and you will need support material across the bridge joining both sticks, but I got away without supports at the control stick cones.

Finally, here's the Fusion 360 design link, I'll be happy to get any suggestions or improvements!