We just moved to Seattle from SF. Highly recommended, but as you say more expensive than Portland (still 1/2 the price of the bay area). Cost follows opportunity, and it is harder to find a tech scene in Portland. NYC is a great place to live (have done so), and I would pick it over Seattle (at least for a year or two) if you don't have kids, are young, and can afford it. Chicago is great, less tech than NYC/Seattle,…
I feel like you might just not know where to look. We have a very thriving tech scene and it's growing very fast. 4,045 job opening as of now. http://portlandtech.org/
http://calagator.org/ is a great resource for meetups, talks, round-tables, sessions, etc.