I can give you some good roads in WA . WA is interesting because one side is desert and the other rain forest.
One of the best roads HWY 20 between Sedro Woolley and Winthrop. Does not open till shortly before US Fathers Day most years. Check here: WSDOT - SR 20 - North Cascades Highway
Been there on fathers day and one year we were riding with 40 ft of snow on one or both sides of the road in some parts.
Chilly (understatement) but incredible at the same time. Do not miss the Diablo Lake Vista Point.
It will be on your right part way up a steep grade. It's a pretty big parking lot worth pulling over to take a look and some pictures https://www.google.com/maps/place/Di...096555!9m1!1b1
No cell service back in there that I am aware of, best to locate the vista point on a map or google before you leave Winthrop.
There are a couple of short tunnels on the road down by the dam past the Vista point. They are unlit. There are caution lights at the entrances. When these lights are are flashing it means there are bicyclists in the tunnel in the darkness.
Riding the flowery trail from Beman Road and HWY 20 near USK to Chewelah is a hidden gem.
Little tricky to get on from the east going west. Hwy 20 to Beeman Rd/ McKenzie rd. Turn left. Your only a mile or so from USK which is to the right (so you can find it on the map) . Follow the road around. Mckenzie becomes West Calispell Rd which becomes Flowery trail. It's a beautiful ride through to Chewelah
There is nice loop from Kettle falls (North of Chewelah on interstate 395) to Republic over Sherman Pass on Hwy 20. Turn on HWY 21 north to Boulder Creek Rd just south of Curlew. ( If you have swim trunks you can swim at the swimming hole at Curlew if you want. It's about 100 yrds north on 21 from the Boulder Creek Road turn off.) Turn right on Boulder Creek Road follow it past Curlew and go over Boulder pass to Interstate 395. Right turn at 395 heading south back to Kettle falls.
Or...... when you get to Boulder Creek RD you could go left. You will be on Toroda Creek rd. Follow it several miles and make a right on the Chesaw RD, (forest road 9480). That will take you past Beth lake and Beaver lake to Cheesaw. Continue through Cheesaw staying on the road till Oroville. When you get gas in Oroville ask for directions to the road to Night Hawk. Continue past Night Hawk, past Palmer lake, past Spectacal lake, then south on 7 eventually ending up on 97 at or near Tonasket. Nice loop, great riding there also. Good food at the Bonaparte lake resort. Google it when in the Curlew/Tonasket area. Att service only in Curlew.
Before leaving Eastern Washington check out Dry Falls interpretive center and the drive along Soap Lake and check out Grand Coulee dam/ Electric City. It's all in the same area.
Sun Lakes-Dry Falls State Park | Washington State Parks and Recreation Commission
There is no lack of good riding in WA just watch your speed on the main hwy's . No lack of tickets for speeding either. $$$
Haven't used the ferries in years but the West side ferries used to be reasonable for motorcycles. Not sure how they are now. Once at the terminal you drove to the front of the line. They loaded you first and unloaded you first. They never used to turned motorcycles away because they always could find a spot for them. Great way to see the San Jaun Islands
then later miss most of the interstate on your way down the coast to Seattle area or Oregon. You'll want to hit the ferry to the San Juans from Anacortes first thing in the morning because the Islands are a tourist site and staying the night was always pricey. I believe you have to pay going out to Friday Harbor and back to Anacortes. Can't remember for sure.
This is from the WA DOT site:WSDOT - Ferries - Anacortes Ferry Terminal
While motorcycles are not, by Washington Administrative Code (WAC 468-300-700), a preferential loading category of users, they are often loaded prior to automobiles for operational and staging purposes. Arrival at the dock after vehicle load has commenced requires motorcycles to wait until all cars have been loaded for the next motorcycle loading opportunity. Motorcycles should proceed, while on the dock, at no more than 10 mph. Use caution when car decks are wet. The following information details specific staging for this terminal:
Motorcyclists queue, along with vehicles, in traffic line prior to tollbooths. Proceed to motorcycle staging area in front of holding lanes as directed by ticket seller or traffic attendant.
Loading order: bicycles, motorcycles, vehicles, late arriving motorcycles as space permits. Space may be limited to 30 motorcycles per sailing.
Here is some more info on the ferry to and from the San Jauns https://www.visitsanjuans.com/transportation
WSDOT - Ferries - Schedule: Winter 2018 Sailing Schedule for Anacortes / San Juan Islands
Don't know if the prices are different in the summer?
Hopefully someone from Seattle area who has used the ferry system recently can chime in and give you more info or correct this if things have changed any.
After your cruise around or on the islands you will end up back in Anacortes you can then head south on 20 using the ferry system to either end up in Seattle or Neah Bay out on the Olympic peninsula. Working your way down across the islands and taking the ferries that fit you needs. The other ferries should be cheaper than the one to the San Juans.
My own preference then would be to head down the Oregon Coast
after seeing Seattle or the Olympic peninsula.
If you plan on doing this trip before July 4th bring good quality rain gear or you will most likely be buying it on the coast. Also long underwear and good socks to be comfortable on rainy days. Those coasties grow webs between their toes for a reason. It is so beautiful you won't believe your eyes though. After July 4th the sun shines mostly till end of August.
That ought to keep you out of trouble for a while. There is a lot to see in WA and across the border in BC also. Oregon coast is to die for and if either of you are aviation geeks check out the Evergreen aviation and space museum down in Ricz neck of the woods just south of Portland. https://www.evergreenmuseum.org/
Go early or be bummed you didn't. You'll need the whole day to see it. Spuce goose, SR71's Migs, ICBM silo and control room. List goes on.