Not that I think moving the event is desirable or even feasible, according to the U.S. Census Bureau, the current population center of the US is Hartville, Missouri, a town of 600. East-west, it's not that different from Oshkosh, though of course it's much farther south, almost in Arkansas.

I wonder what the population center of homebuilt aircraft owners in the US is? There must be a way to convert aircraft registration zip code in the FAA database to lat/long and find the average. Ron, you're the database expert...