U think BTC and Eth are different. The price of BTC is not stable and Eth has the price of stable, but the price of BTC is higher than Eth, although BTC is decrease 
Ether isn't stable once bitcoin goes on another dip all altcoins including ether will follow the same kind of movement. There are other alts that are much stable than these two but I won't talk about it. Ethereum can take Bitcoin's spot but not right now maybe in the future who knows. A lot of altcoins have been rising up recently and we might see one taking over Ethereum's spot.
Eth is 1st for the fast transaction , but the value of bitcoin is the first to all the altcoins . Maybe if bitcoin is going down to 1k usd , we can that call eth higher than btc . But wait for the pump up of bitcoin or dumping.
No way bitcoin could go down to 1k. If that happens ethereum would also go down to $50- $100.ETH can't take bitcoin's position but it will get very close to bitcoin if the market goes like this. The difference between them is less than 2x market cap now.