Charlotte is really interesting. It's very evenly distributed, even compared to Boston. It's also not balanced on the north / south axis. Are there more north bound one way streets?
Downtown Charlotte is definitely a strict grid pattern. I think Charlotte is more a victim here of having really widely defined city limits than anything else. Do a graph of just downtown Charlotte and it'd look just as much like a strict grid as Manhattan does (which, worth noting, is not all of NYC).