In the past I have always taken the eastern route from Calais to Beziers via Macon, Lyons. This is mainly because I wanted to avoid paris. Is there a better route, avoiding Paris and will it save much time?
You do - but it isn't as bad as it sounds. I usually pass through at 8.30 in the morning and it's always 'fluide' You have a choice of two routes - one each side of the river. One of them passes through a long industrial estate and eventually leads to the A13. The other, the N15 mentioned by Val is also the one I prefer. Incidentally it's now designated the D915, and even the D6015 in some sections.
The route takes you through Pont de l'Arche where there's a Super-U just off the roundabout. They have good fuel prices with a caravan-friendly exit.