There's also the problem of fossilized borders and jurisdictions that no longer reflect current realities. It'll never happen, but some realignment of current state borders would probably be beneficial. There are the lurking proposals to split California into multiple substates. The New York metro area has more in common with its neighbors across state lines than with the people in the hinterlands of their respective states. In my home state, we have one small urban area that can effectively wag the dog of the rest of the state and ramrod through any ill-conceived notion that catches its fancy, with terrible consequences for the rest of the citizens living outside that bubble - on any election, the returns are nearly mirror images of each other for that one enclave versus the rest of the state.