Pithecanthropus takes the PNW. Need one-way flight+hotel recommendation

The Pithecanthropine vacation is finally set. After several changes of plan, we’ve finally decided, booked, and paid, and on May 10 we will be embarking on the Zaandam for a four-day voyage to Vancouver. We’ll spend one night in Vancouver, where the cruise line will arrange a hotel. The next night we want to spend in Seattle so as to catch the Coast Starlight on the following morning, to return to L.A.

So we need a one-way flight from Vancouver to Seattle, plus hotel. Can any of the online travel services do this? Or is there a better way to go than flying? I don’t imagine it’d be possible to rent a car in Vacouver and frop it off in Seattle. And as far as I could find out there’s only one train making the trip each day, not at a really good hour.

And what’s the one thing we shouldn’t miss in Vancouver or Seattle?