There are some lovely bits of France with some really nice roads but, for me, you need to get close to the Pyrenees or, better still, the Alps, to get the really stunning scenery that's around virtually every corner, and the breath-taking roads that can be ridden fast, slow or anywhere in between, and still be hugely enjoyable.
Having spend many trips exploring bits of France north of Paris, I came to the conclusion that, if you're into WW1 and WW2 history then it's a great place to go but if you want breath-taking scenery then get on the autoroute for a day and get to the Alps. From there ride the Route des Grandes Alpes and the route Napoleon. Visit the Gorge du Verdon and the Combe Laval balcony road.