Lucky people. We've just spent a month in France doing the Canal du Midi from the Med to Toulouse where it ends. Then along the Canal de Garonne as far as rental boats are allowed to go towards Bordeaux.

A great place not too far from where you'll be starting is Aigue Morte. Medieval walled city on the coast west of Marseilles. Sort of a small Carcassonne. Over in Burgundy your idea of Dijon or Beaune as a base is perfect. I haven't stayed there since my honeymoon many, many years ago so I don't have any hotel or restaurant recommendations but it is a wonderful area.

Basically France is a magnificent country and there are just so many places spread all over it is difficult to do it justice in just a few weeks. I like just having a car, driving and then stopping when we find somewhere we like the look of. Get the Logis de France hotel guide (or app) and Relais et Chateaux for more expensive places and just explore.