Many, many, moons ago, when I used to fly R/C Sailplanes, the AMA (Academy of Model Aeronautics) which holds a "Nationals" contest every year did a bit of a study when looking for a site.
There were a number of sites available, and it was determined that the Dayton, OH site was the best available, as it was within one day's driving distance of a majority of the population of the US, and would make it easier for most modelers to attend.
With that in mind, I'm thinking that the Columbus Ohio area might be considered.
I know that last June, there was a VGTCOA show in Plain City, Oh which is within a rock throw or two of Columbus.
Maybe DougT can help us out with more info on that, as he was the organizer of that event.