both are equally good. the difference is their value. bitcoin value is greater than the value of ETH. because the value of bitcoin is greater then the profit of bitcoin is also greater than the profit of ETH but the risk is also greater than the risk of ETH. example 1 BTC vs 1 ETH. for example, the value of both goes up 1 level, 1 BTC ($ 8000) and 1 ETH ($ 600) if both go up 1 then become 1 BTC ($ 9000) and 1 ETH ($ 700). you can earn $ 1000 profit from BTC and you can get $ 100 profit from ETH. bitcoin will be more profitable. but if their value drops 1 level then BTC risk is greater than risk of ETH. you can lose $ 1000 from BTC and only $ 100 loss from ETH.