Can't help with the CA sections but once you hit Oregon on 101 stop at the first visitor center ( if you haven't got one earlier and pick up a "Mile-by-Mile Guide" for the OR section of 101. It is extremely useful as you travel that coastal road.
Washington section of 101 spend quite a bit of 'time' away from the coast but some great places we like to visit in WA are Ilwaco and Long Beach, at Raymond swing west on 105 for the coast to Aberdeen.Ocean City is unique. Then north and back to the coast at Queets and north. At Forks (just north) take 110 west to LaPush. The native tribe have a very nice CG there.
At Sappho take 113 and then 112 out to Neah bay. If you are up to it take the boardwalk out to Cape Flattery! back on 112 east to Port Angeles and Sequim/ Olympic National park. then south along the Hood canal to Olympia and I 5.
Have a great trip on one of our favorite drives!
John