Two constraints conflict: visiting both New Orleans and Houston while keeping every single day under 4 hours of driving is not possible because the New Orleans → Houston driving time is roughly 5–6 hours. Also a few other legs (Washington DC → Clemmons and Clemmons → Great Smoky Mountains) are borderline and may exceed 4 hours depending on route and traffic. Tell me which option you prefer below so I can build a detailed day-by-day plan with activities and meals.