You're doing that at the right time of the year, that's for sure.
I'd suggest Hwy. 1 from Wash. all the way down to Calif. Just a few miles south of Eureka, Ca. you may want to swing over (seven miles) to the town of Ferndale, Ca.
http://victorianferndale.org/chamber/ All the buildings in town are Victorian.
Once you're back on Hwy. 101 you'll want to take the first exit that says "Avenue of The Giants" and follow that road all the way to the other end (31 miles, but you'll want to stop a lot).....
http://avenueofthegiants.net/Continue south on Hwy. 101 to Willits, Ca. then turn west on Hwy. 20 for one of the most incredable motorcycle roads in this country.......45 miles of twisties in a beautiful forest and incredable views all the way to the ocean and Ft. Bragg.
From there you'll head south on Hwy. 1 and some of the most incredable coast line from the Canadian boarder to the Mexican boarder. You'll pass by Point Arena Lighthouse (a couple miles off the Hwy.) but it is open to the public and they even have lodging in the keepers old residence......
http://www.pointarenalighthouse.com/lodging.html A few hours further south on Hwy. 1 you'll pass Point Reyes Lighthouse.
South of San Francisco on Hwy. 1 you'll travel some more great cliff hugging roads along the coast and will pass more light houses and more places you'll want to stop.