Yes, Ethereum is still the king as no other platform has shown the adoption yet which ethereum has.
Ether price has been declining mostly for two reasons:
1. Firstly, the introduction of a new BitMEX - ETH perpetual swap contract, which allowed traders to shorten the price of ETH with up to 100x leverage in a similar manner like the XBT (BTC) BitMEX contract. Although this has not been confirmed, this statistic has led to the speculation that the arrival of the contract allowed pessimistic investors to weigh down on the price of ETH.
2. The ICO sell-off factor, with many traders claiming that projects have begun to liquidate their war chests, that are often full of Ether, into fiat, leading to the current collapse of the market, not only ETH.
The chances are it would bounce back quickly and its just for the short term.