Anywhere on the coast that isn't a tourist trap, Mt.Hood, The Gorge is a must. Eastern Oregon has lots of desert country that's way cool (Smith Rock for climbing). Portland is OK, but Eugene is better.
You should go to Ashland, it's my fav. place in Oregon. There is a little downtown and good ganja. Lots of kind folk. Also this little place on the coast called the hobbit trails. it's slightly north or florence.
Totally forgot about the dunes and I live in middle of them...Yeah, the dunes are great but the towns that surround 'em suck. Crappy little tourist traps and crack havens
I've had a number of friends who lived in Bend, Oregon and absolutely loved it. Ofcourse these are ski bum friends of mine who were there purely to ride Mt Bachelor, but they gave the town good reviews as well.
Go to the Largest Spruce Tree in the world, just south of Seaside Just north Of Cannon Beach. The Seaside Hostel is the cleanest hostel in the world, i used to work and live there. There's cool campgrounds with cool people all over the north coast. Haystack Rock on Cannon Beach has lots of beautiful sea life in the tide pools. Astoria is where the Goonies was filmed and is known as the little San Fran of the northwest. There's cool bars and people and a syndicated Utah Phillips show, Loafers Glory braodcast on Saturday nights from Astoria, Dan in the hostel listens to it in the common room by the fire every week.