I agree that 2018 will be a great year for Ethereum development-wise, but it may very well be the opposite for the price valuation. There is no clear explanation for the valuation of 1 ETH yet, and so far that means it remains pure speculation. Considering the fact that many people are already speaking of a bubble, I would remain cautious making any price predictions. But price might get higher if staking gets implemented in 2018; so get ready to see the mother of all FOMO: reduced available supply to sell (due to staking), dividend pay-out . These two situation would create a fairly strong positive feedback loop: People wanting to buy eth because of the dividends, but less eth available for sell due to staking, all of which lead to price increase and feeding this looop!