The coast road is not improved by speed. A good day has fewer miles than expected and more moments where the car is parked before the view fully arrives.
Fog changes the route in useful ways. It can hide the obvious photograph and push attention toward sound, short trails, and the small towns that sit just inland from the cliffs.
Plan one real stop before lunch and one after. Everything else should be optional, because the best part of a coast route is often the unplanned pullout that earns twenty quiet minutes.