OP: You were concerned about your 32' RV. Don't be. It's a baby. :) Our 40' motorhome fit everywhere we wanted to be.
For the coastline I'd highly suggest you pick three places to stay - the southern part, midway and the northern part. Then you can cover the whole coast by doing day trips.
We really enjoy the state parks on the coast. With our 40' we've stayed at Cape Blanco (excellent) and a favorite of ours. You have huge sites, a peaceful area, a lighthouse and a gorgeous beach almost to yourself!
Other state parks we've stayed are Beverly Beach, Bullards Beach, Carl Washburne, Harris Beach and Fort Stevens.
Make it a point to tour the lighthouses along the coast. We gave the tours at Heceta Head - a beauty!
For Washington we've always enjoyed staying in the Port Townsend area. Fort Worden State Park is a great place to stay. It's a neat little waterfront town with lots going on. From there you can easily take the ferry for a day trip to Victoria, British Columbia. Hop on a public bus to take you out to Burchart Gardens.
Another day drive your vehicle up to Hurricane Ridge in Olympic National Park.
Still another day drive a little south to Bainbridge Island, park your vehicle and pick up the short ferry ride to Seattle. You'll get off near the Aquarium and Pikes Market. Pick up the monorail that will whisk you across the city to the Olympic Space Needle. Return to Pikes Market for a little shopping before boarding the ferry for your return. It makes for a very pleasant day - all from your campsite in Port Townsend.
I hope you make the effort to go there. You'll love both Oregon and Washington.