We try to drive down to Seattle and Portland somewhat regularly. We like them both.
In Seattle, we generally centre our trip around a visit to Pike Place Market and the area around it. Pike Place Chowder is a must. We may walk down to the pier (which is being redeveloped) or walk over to Westlake Centre and/or Pacific Place mall. We occasionally walk over to the International district and Pioneer Square area to check out the shops and restaurants.
Not sure if a stadium tour or taking in a Mariners or Seahawks game interest you but they're really nice stadiums. While walking around to various destinations around downtown, we find there are a number of dead zones (at least during the weekend).
We also like to track down farmers markets which have led us to different neighbourhoods. The one in West Seattle is small but driving around the neighbourhood along the water is nice. We also frequent one in the University District which also has a bit of a retail area nearby.
We don't do a lot of shopping in Seattle. We'll typically hit Seattle Premium on the way down or venture further south to Southcenter Mall.
We hit up a lot of different fish & chip, chowder, and pizza places when visiting Seattle. One quirky place we like to eat at when the timing is right is Maneki.
One area on our list we never get around doing is walking around the Space Needle, EMP, and Olympic Sculpture Park.
Lots of potential destinations in Seattle along some body of water.
In Portland, we generally centre our trip around a visit to the Farmers Market around PSU and the Saturday Market along the Willamette River. We'll also walk around Pioneer Square which seems to frequently have activities happening in it. There's a lot of retail along the square too. We'll also walk around the Pearl District.
In Portland, what drives us to visit areas outside of downtown are food cart pods and restaurants we're interested in. There's generally two areas we'll regularly visit: NE to Mississippi Ave and east along Hawthorne. Mississippi has a bunch of small shops and restaurants with a food cart pod at the end.
Along Hawthorne, there's a food cart pod along 12 Ave (with two of our favourite carts: Potato Champion and Pyro Pizza). Further down, we'll visit Apizza Scholls. We just find Hawthorne an interesting street to walk or drive along.
Other food places we try to hit up are Olympic Provisions and Laurelhurst Market among the various the various food carts on our list.
We seem to run across a lot of festivals and events when visiting Portland in the spring/summer like a craft beer fest, food cart fest, street art festival (Art in the Pearl), etc.
For shopping, our primary destination is a run south to the Woodburn Outlets. Along the way, we may stop at Bridgeport Village, an outdoor mall. The "regular mall" we usually visit is Washington Square. We may also hit up the Nike Outlet but it's not a special outlet.
Quirky stuff we like to do include stuff like playing video games at Ground Kontrol, buy doughnuts at Voodoo (really touristy), get lost in Powell Books, etc.