I was looking at the map of where MLB teams are and you have Seattle up there by themselves in the upper northwest with nobody else close. I guess there isn't enough population in states like Wyoming, Oregon, Idaho or Montana for teams. If they can't support a team then it looks like North Carolina would fill a big gap. A second team it looks like San Antonio would work as far as filling in an area that doesn't have a team even though there are already two on Texas.
Half the teams in MLB are either between DC and Boston or around Lake Michigan area. Other than that teams are spread out.
