Here are some early render concepts of what the final device could look like. It should be quite compact and fit easily within a gripped hand. It tapers slightly as it rises in what is hopefully a comfortable shape. The joystick is angled towards the thumb to provide better reach. The holes in the sides of the casing are where straps to attach it to the hand could be threaded through to be bottom of the device. I expect there will need to be many refinements here to ensure the ergonomics are good for a variety of hand sizes.

The bottom-most button on the back of the device is ostensibly the ‘mode’ button to cycle presets, but can be remapped, like all the others, to be anything.