If we can get AR with the quality of the occulus rift, gesture control with very fine precision and an emotiv like layer for added thought interaction, for 300$, I think we might slowly be getting somewhere...
Offer me such a controller with multi-platform support and I'd buy it at <800$. I think that's a good price to pay to add immersion capability to an Xbox, PC and PlayStation.
And I'm not even a gamer anymore.