If somebody started pushing it hard now, it probably wouldn't come to pass in my lifetime, but...I think maybe we should get rid of some or all of the states.
The more I study U.S. law, the more it seems like the biggest flaw in terms of efficiency is the state system. Modern transportation and communications have made the country smaller and smaller, yet we still have these 50 sets of laws made up to conform to the supposedly unique character and makeup of all these different states. But the states are getting less and less unique, and it costs a whole lot of time and money to administer 50 different legal systems that are different for no good reason except tradition and because we like the "S" in "USA". Then you have a federal system that has to wade through the muck of all the state systems (c.f. Erie problems and pretty much all jurisdiction problems).
It could be argued, on the other hand, that if you get rid of the states, you don't really save anything. You either just shift lots of power to the federal government, which is far more detached from where the action is and potentially far more inefficient, or you create a jumble of thousands of city or county governments that would develop an even greater number of bodies of law.
I think there's an economic argument, though: one state may not be the most efficient or desirable number, and 1,000 counties with the power of states may not be efficient either. However, there is some number in between that is best, and there's not much reason to believe that we magically hit upon the lucky number of 50 and it's just perfect. Maybe we had the right number when we were at 13.
The political resistance to this would be enormous, but I think we could save a lot of money and hassle if we could consolidate some of the states, especially the smaller and less populous ones. What if we consolidated states along the lines of the Circuit Courts?
I guess it's obvious that I think that by this point the idea of 50 independent countries all getting together into one groovy federation is a silly, outdated and overwhelmingly costly fiction.
Okay, now let's see if I ever get elected to public office!