Hi Sandbox and welcome! If you scroll up and down in the forum you'll have plenty of reading about the pros and cons of agency...Seattle is a gorgeous part of the country!!
There were lots of agency jobs posted in the Seattle papers so I'm sure you won't have trouble finding work there per diem or contract.
All agency work has the occasional 'dry spell' which we get used to and plan for. The biggest pro for me is the ability to stay out of politics and not get 'sucked in'...which is always a major energy drain for me (and many nurses)....and why we like agency.
Those of us who like agency are independent, confident and flexible and don't need a solid relationship with the staff to give good patient care and be happy in our career. We thrive in varied environments, and enjoy travel. I have friends who really thrive on familiarity... they would never do agency work. We're all different.
We get dumped on occasionally...but we never have to go back either. Big plus for perdiem work.