I recently hosted a couple of visitors and thought you might like to see our itinerary. One has a career in the arts and has traveled extensively but never to Seattle, and the other has been to Seattle several times, but never in summer.
They said they were interested in gardens, art and museums - especially things they had not seen before, theater, scenic views, the Asian immigrant experience (have read Jamie Ford's books), the working waterfront, and historic Seattle. They were up for walks but not hiking. They were interested in moderate dining and do not follow food trends. Washington wines were of interest, but not spending time at tasting rooms. They had full access to a car and driver (me!).
It was a great week!