You have a good point, but it's a tough sell.
Nothing will likely be done until, as in 1787, our backs are against the wall. Back then, adults took the reins, and lead a willing people to a government that suited them.
My fear is that we will not take action to repeal the 17th in time. With our backs against the wall again, I think our corrupt society will go the way of the French Revolution instead.
As for hacks in State legislatures, the federal system worked well enough pre-17th. The Framers accounted for such men. Yes, a tough sell, perhaps impossible, but wouldn't it be great to control the debate instead of being on continual defense?