Interestingly, the concern about large/small states, and north/south states, should probably give way to an unconsidered grouping, the east/west states.
Instead of worryiing about the localization of power and wealth around the center of government, I think as the country expanded the localization occured on the eastern coastal states vs. the western states.
If you consider that we have four continental time zones, it only makes sense that the country wakes up on the east, and all power begins while the west is still asleep. The leading newspapers are the New York Times and Washington Post, all television is based on the Eastern time zone broadcasts (even live western events are timed for east coast consumers).
The major financial markets are in the east as well. The New York Stock Exchange closes at 1:00PM PST.
So, I'd say yes, centralization has come to pass, but it is east vs. west today.
-PJ
I like the way you think.