Can't wait for the eye tracking of the Apple VR headset as described in this video to become more common https://youtu.be/OFvXuyITwBI?t=228 seems like the most ergonomic way to interact with the computer
I find eye-tracking interface to be very clunky and constraining. You have to restrict where you are pointing your eyes, or you will select things by accident and then you'll miss what's going on in the world. I think any prolonged session will give people eye-strain. 3D goggles already do. With eye-tracking doubly so.