It's a funny old thing but my favorite biking roads in France are not in the Alps, they are in La Region Centre - especially round Sancerre. Every road round there is a beauty with a lovely variety of corners and the most perfect surfaces. The French lads on their Z750's tear up the place but you very rarely see British bikes round there.
Granted, the views in the Alps are worth the trip but often the famous passes are blast-hairpin-blast-hairpin. They're also full of cyclists. And I refuse to ride fast past a cyclist, as cycling in the Alps is another one of my favorite pastimes.
Those quiet, rural, non-touristy bits of France are relatively undiscovered and offer a cracking challenge. Do 300 miles in a day on those roads and you'll sleep well that night.