The other thing is -- it's hard to get things done in politics. Major changes only come around once in a generation. A minority party can't get anything done in any case. But in practice you need over 60 seats in the Senate to pass significant laws. That happens very rarely. I doubt Boehner and McConnell would exercise much leadership even if they had those 60 votes, but without them, there's not that much that they can do to change things.
It does not take 60 votes to REFUSE to pass things. But then, oh no, shutting down the government, yikes!
Boehner et al could at least stop giving the minority opposition 60 votes.