I predict Ethereum will someday overtake Bitcoin. Realistically, it is just a lot better of a cryptocurrency all around.
ETH is something that has been serving as the alternative for the bitcoin. Ethereum slowly gaining more power and the same won't replace the bitcoin growth. Ethereum has been gaining more potential as more and more ico tokens were getting developed on the same Eth platform.
I don't really see Ethereum being the platform of some coins affecting the price of Ether. Maybe it helps keep Ether in the scene of things but at the end of the day, just because these coins under ETH contract are getting some light and some hype, it doesn't really increase the price of ETH. Right now, even with the thousands of coins under ETH contract, ETH is still going down while bitcoin's price is going up. It seems like ETH is just another altcoin, right? Just like any other, ETH is affected by bitcoin's movements and there's no stopping it. Not with these little coins under ETH contract regardless of how many coins are they.
Bitcoin is the base currency of the cryptoworld. Its movement is affecting the price of all the other coins. And no matter how much these new coins get in their ICO or how much hype they get in the trading world, at the end of the day bitcoin will always be the king. After a long time of trading altcoins, you will still convert them to bitcoins in order to cash them out and use some money in the real world. No coins have come near bitcoin's standing in the crypto world and I don't think there ever will.