We hope to spend 6 days in Provence in October, perhaps with a rental house in Cassis as a base. My questions are: Is Cassis the best base for touring Provence? We really want a sea view!
What is your list of "must see" vs. you can "skip that town" in the area?
My list would be Arles, Avignon, the Camargue, le Pont du Gard and Nimes in the Gard area and the Camargue. From Cassis, you should be able to go to the calanques if it is not too windy. We LOVE the Luberon area. All the little towns are so special and each is unique. Gordes, Roussillon, Menerbes, Bonnieux, Ile-sur-le-Sorgue. Others will praise Vaison-la-Romaine but that wasn't our favorite. It seemed very crowded any time we were there. Of course, all the other little towns can be very crowded on market days. A lot depends on if you have a car or not. You may need to just sit down, look at a map and pick one or two places to see with the thought that you will return!
We rented an apartment in Lourmarin (Luberon) for 5 days after two on the Med in Le Lavandou and before 3 in Vaison-la-Romaine. We agree with previous poster that V-la-R wasn't our fav, although we loved our B&B, L'Eveche. We liked the sandy beaches of Le Lavandou, and I loved the fact that no English was spoken-so I could use my French I'd practiced. More access to more of Provence from Lourmarin than Cassis IMHO.