I do have to say that Quaternion controls really well with a controller (as long as you have betterDS4, dang devs not supporting dualshocks). I do have a bit of a concern involving the vibration on the controller, however.
As you may or may not know, the controller vibrates whenever your marble is rolling. This is extremely uncomfortable and distracts me from playing the game. I would appreciate if you could rectify that in a later release.
Keep at it, Whirligig. I'd love to see where you can take things.