Lived here for 25 years. Moved away 10 years ago. Back for extended stay visiting old friends. Changes, of course, some for the better, some for the worst. Has grown, with more things happening but more traffic.
Pro's: Medium size city with enough art, culture and so forth to keep most people happy. Moderate traffic jams. Excellent public transportation. Good schools and educated populace No sales tax. One plus hours from mountains and skiing, from Pacific Ocean (although too cold and rough to swim). Clean and green. Fantastic "foodie" scene, heavy on the locally grown thing. Folks polite. Grow almost anything except tomatoes (not hot enough). Government efficient, not corrupt. Three months of the year the best weather in the world. Very excerise friendly, with bike lanes, hiking trails, moderate weather. Some of the most beautiful scenery in the world, with the Columbia River Gorge, Mount Hood and the Oregon coast. Beautiful geographical setting.
Depending: liberal, left coast politics, major hipster population. Businesses heavily regulated. Those with allergies might find it tough going.
Cons: Steep, progressive state income tax. Very expensive housing, including cost of owning or renting, property taxes high. Locals somewhat slow to make deep friendships. The weather nine months of the year? Awful. Rainy, gray and gloomy, chilly, foggy, overcast. That's why I finally left.
Ideal? Summer in Portland, winter in Mexico or some such place.
Hope this helps.