ETH is a different type of coin to BTC, so they shouldn't be seen as direct competitors. The selling point of Ethereum, the use-case, is that it is a smart contract platform. BTC doesn't offer this functionality.
Nevertheless, it is Bitcoin for the entire cryptocurrency market, and this despite the fact that almost more than half of all cryptocurrencies are created on the erc-20 platform. I think that exactly ethereum should occupy a leading position in the cryptocurrency market.