I go with the one with higher value. Common, increase in Bitcoin is a 7000% increase in dollars currently. Why look into increasing my dollars when I can kill two birds with a stone throw of  increasing my bitcoins which will in result increase my dollars. It's just like saying which is preferable between Gold and Money. Gold increases in value while money does not. Bitcoin is in a way synonymous to Bitcoin. Whether you work to increase it or you just buy and HODL the value has the potentials to hit the sky anytime. But Dollars will remain dollars for life, as it's value is a fixed one.