Originally Posted by
mtnbud
Eastern WA and OR are beautiful in a different kind of way, but it is a lot of nothingness, heat, and dry grassland. I agree it might be nicer to head directly West from Spokane.
Northeastern WA is very beautiful.
I'd recommend heading Northwest to Curlew and then Winthrop. From there maybe take a ferry over to Port Townsend. You could also head up to Canada and then head West.
I've gone through Northern Washington, and would definitely recommend it above going south or west, especially if you have the time (and it sounds like the OP does.) The main issue with that route, though, is timing: If the OP intends to set out in April or even May, SR 20 (North Cascades Hwy) will still probably be closed over the Cascades, and there will probably be still snow on all the other high passes SR 20 crosses (and there are many passes.) Heading out to the coast via the Columbia River would mean avoiding cold and snowy passes.
One other thought: If the OP wanted to head more due west than south from Spokane, an issue will be the few crossings of the Columbia River north of Pasco. I've never ridden Vantage Bridge, I-90's crossing over the Columbia, but from all reports from other cyclists it is not fun, since there is barely a shoulder and traffic moving at freeway speed.