I think that Buterin is smart enough to understand that it's necessary for keepeng confidence in ETH to increase the price. So he and Ethereum Foundation will do whatever they can to increase the price. I hope it will reach 1000$ till summer 2018.
I don's see him interested in rising ETH price. Volume - yes. But not the price. ETH will be somewhat about $300 next year because owners are not interested in making ETH another coin for speculations.