I think you'll find Haceta Head just halfway between Florence and Yachats not north of Newport and it is worth a stop. There is a day use area below the lighthouse. The Oregon Coast Aquarium on the south side of the river in Newport is also worth a stop as is the waterfront of Newport. Beverly Beach north of Newport is a great campground as is South Beach just south of Newport. Yachats is a quaint little village but we haven't eaten there since we sold our home there 18 years ago. The state park(no campground) I nice for tide pools and south of the river for beach walking. Just a few miles north is Waldport, some campgrounds there(up river and a very expensive KOA) nice beach walking at Bayshore north of the Alsea River. Lot's of places for crab in Waldport and crabbing on city pier with rented gear in Waldport.
Florence is sort of home for me and sand dunes are a must. The south jetty is not part of the Sand Dunes recreation area and is free, don't pay the entrance fee. The north jetty has miles of dunes and lots of driftwood.
We don't recommend Mo's anymore since Mo died the food has suffered. BJ's ice cream is great and Old Town is nice shopping. Honeyman's State park is nice but hard to get a space. I could go on but I'm off to the dentist.