The only regions that are more expensive than us-east-1 in the States are GovCloud and us-west-1 (Bay Area). Both us-west-2 (Oregon) and us-east-2 (Ohio) are priced the same as us-east-1.
I would probably go with US-EAST-2 just because it's isolated from anything except perhaps a freak Tornado and better situated on the eastern US. Latency to/from there should be near optimal for most eastern US/Canada population.
