I would suggest doing the "coast", from the I95 Yemassee, SC exit, on the 17 as a start. We stayed at the Point South KOA (in a cabin) on the way to Florida in January. VERY unusual KOA, for adults (there is a nice pub & excellent baked pizza right in the main office; with wine tasting at the in-campground wine bar). This is fairly close to Beaufort.
Then, drive the 17 on through to Charleston (now, you're on the coast), and on to North Santee, and Murrels Inlet, NC. Shoot through Myrtle Beach, heading north to Wilmington, NC, then on through to Jacksonville, NC. Here, you can decide if you want to go to Cedar Island, and onto the Ferry to Ocracoke Island (the Outer Banks); and onto another ferry to Hatteras, and drive the Outer Banks all the way up to Kitty Hawk (where you can pick up the 17 again in Elizabeth City, for Norfolk VA), or, in Jacksonville, NC, continue on the 17 up to Elizabeth City, then on to Norfolk, VA. In Norfolk, we habitually stay at 1st Landing State Park (very large sites, along the inlet/outlet of Chesapeake Bay.
From Norfolk, take the 13 / L. J. Kellam tunnel/bridge (roughly 20 miles long+/-) across the Chesapeake to 13 north. Along the 13 to 113 you can stop/stay at Assateague State Park (on the ocean). Super nice locale. Then, head north again along the 113 up to Cape Henlopen (an excellent and unusual State Park we stay at often). Then, from near-by Lewes town, you may opt for the Cape May ferry over to North Cape May, NJ.
At this point, you have bypassed Richmond, VA, Washington, DC, Baltimore, MD, and most of Delaware. From North Cape May, you could head up the Garden State Parkway, to the Atlantic City Expressway, to the New Jersey Turnpike (the NJTP will be your best bet for urban driving to bypass Philadelphia, Trenton, Newark, and New York City, IF you then take the I287 through Bridgewater, Morristown, Mahwah, and onto the I87. The I87 from junction of I287 is quite scenic, going through the Catskill Mountain range. At this point, you are quite far out from any urban areas.
Just before you hit Albany, bear off the I87 at the 912m towards East Chatham (now you're on the I90) but exit onto I90 towards Albany; then almost immediately, take Exit 12 onto Highway 9. Where Highway 9 intersects with Highway 20, take the 20 towards Nassau, and continue all the through to Pittsfield. At the intersection with Route 7, head north on Route 7 into Vermont, towards Bennington, VT. In Bennington, you can take the mountainous route on 9 then 202 over to Concord, NH; or, you can continue on Route 7 north up to Rutland, VT, and in Rutland, take the scenic over-mountain Route 4 through Killington, through Woodstock, VT to White River Junction (NH), and jump on the I91 up towards the very scenic 302 into Bath, then Littleton, then Bethlehem and into the spectacular White Mountain National Forest. There are all kinds of rough camping locales through White Mountain National Forest. Once you exit White Mountain National Forest, you enter Conway, NH, then you cross into Maine at Fryeburg, and into Maine "lake country". Take the 302 across Maine, and you drive under I95 (underpass) to Allen Ave; hang a left, and Allen turns into the 100; take the 100 north but here you need the GPS to get you to Falmouth (lots of turns and stops). Once in Falmouth, get on the coastal Rout 1 up to Freeport, ME. At Freeport, you can take Bow Street to Flying Point Rd out to Recompense Shores Campground. Recompense, IMO, is the most spectacular campground in Maine. Many of its sites are directly on the ocean (Casco Bay). The sites are huge, very private, and the grounds around the facility are spread out over 600 hilly scenic acres.
We've done all the above (numerous times). Your mileage may vary, depending on what time of the summer you tackles several legs of this very back-road expedition, for the most part.
