Eric, to your questions...
I don't think I'd do anything different - per se. I would though make the recommendation to pick up a South Carolina road map - even something fairly basic. As noted on the ACA maps, the numbers are a bit confusing - some change according to the different counties, others based on how the wind blows... Well, not really, but it might help in terms of asking for services other than what's shown on the ACA maps. Some of the locals weren't terribly familiar with some of the road numbers ACA printed, nothing serious, nothing tramatic, just an FYI.
Also, absolutely, go along the Outerbanks. Even riding through there pre-season (summer season) it was really super nice - roads, people, obviously scenery - the ferry ride is a nice way to relax. As for services, I used ACA listed services officially, with a more than a few wild nights spent on the side of the road (well hidden would be another way to say it...) in GA and SC. In fact, most everyone I met - including local police - were incredibly receptive to me ditching for the night here or there. As with most areas in the country, the smaller the town/village/whatever, the more likely you'll be to find something you'd normally never expect - like a nice place to camp.
Should you need a bike shop in or around Statesboro, GA as you're making your way, the one listed (don't have the name in front of me...) is outstanding. Super laid back, been around forever, etc, etc. There's also, I think, a shop listed in Suffolk VA (which is off-route about 10 miles or so) that is awesome - same thing, laid back, been around since the stone age.
Enjoy yourself.
Jason