North Carolina: the state owns all the roads, so they're almost all "paved." There may be chuckholes large enough to swallow a dump truck in the mountains, but they're still paved. Exceptions are federal roads (forest service roads, national park roads, between state roads and the Blue Ridge Parkway, etc), which may be gravel.


In Tennessee and Alabama, most roads are paved. If it's gravel, it's probably a driveway, dead end lane, or forest service road. It's worth consulting a good map to figure out if that nicely paved road goes anywhere besides down a steep gully to a dead end.


Tennessee's major U.S. highways have been getting four-lane treatment the last 20 years, usually with shoulders. Stay off two-lane U.S. highways there to the extent possible, unless it's adjacent to an interstate. State roads are usually good cycling choices away from major towns, good pavement and low traffic. County roads run the gamut.


Alabama, stay off U.S. highways to the extent possible (unless adjacent to an interstate). State roads are often viable >30 miles from a city, but if there's a county road parallel, take it. County roads are often surprisingly good, except when they're awful.


OT, I think the variability in how a region treats its roads is one of the big things that makes people either embrace or scratch their heads at the gravel-grinder bikes. If you've got miles of scenic gravel roads nearby, they're great. If the gravel roads in your area go 50 yards around a curve to a gate (and it smells like sour mash -- run away!), there's not much reason to get excited about gravel-grinders.