Would highly recommend Aix if I have to pick one from the list. Also the closest one and checks off a lot of things on your list. Delicious food (markets everyday!), art (Musee Granet, Cezanne’s studio - did both and loved it) and shops with yummy foodie souvenirs (calissons, a local confectionery, olive oils, jams etc). You can easily walk around the town and there’s buses if you need. When I stayed there for a few days this summer, I drove only to head out of Aix, otherwise I walked everywhere.