Train from Paris -Avignon and after a week of St Remy as our base & driving to various towns

each day, where would be a recommended different city to drop off the rental and take the train back to Paris. Or should we just return the way we came? Most of the planned-to-visit towns are around St Remy/ Sur La Sorgue. We haven't planned any towns on the coast (but we could). We have two weeks but would like to stay a couple of days in Paris before flying home (US).