Auto-Owners was my first thought as well. When I was an independent agent (in Georgia) I was also licensed in NC and AL just to sell Auto-Owners policies in both states. Their preferred risk company, Owners Insurance, has great personal auto rates in NC. Auto-Owners Insurance itself has fantastic rates for customers who qualify for their Preferred tier and their Standard tier is pretty competitive with clean credit.
Other than A-O, Cincinnati also comes to mind. Their personal lines rates are fairly competitive in GA, but I'm not sure about NC. They're a great company, though.