there is only one king now and that is bitcoin. so far, no one even got close to him for any indicators. this is especially true of the price. but Ethereum firmly takes the 2nd place in the rating of cryptocurrency.he's more of a Prince.
No one can say in advance what the future, today BTC is king in the market but in the future they may fall sharply and ETH will rise to the throne. So I do not believe in any coin other than ETH. They are the potential coin, most popular now and in the future.