No need to purchase an excursion unless you want to get further away. Everything is across the street from the dock, literally. Wear walking shoes!
Port Grimaud is not a far bus ride and it is a village of multi-colored houses built into a man-made canal system similar to Venice. A few cars can cross the little bridge and drive partway in, but most have boats tied up to their yards. Very quaint and mostly deserted. Only a few year-rounders stay. Again, no celebrities! However, my roommate and I climbed to the top of the old cathedral (for a euro), using an old iron round staircase. Bums of steel, that's for sure! On top, we were treated to a great shot of the sun breaking through the storm clouds making a great photo opportunity. My roommate is a professional photographer and went a little crazy. Got some great photos though!
Aside from the Spanish on the bus that were quiet for their tour info and very loud for ours, the trip was pleasant.