Your turn will come soon.
My green card was employment based and I don't have any complications like traffic tickets or stayed out of country for too long so my interview was very straightforward, probably one of the simplest cases from interviewer's perspective. The only question related to my job was if I am still working for the same company and the answer is yes.
I don't know anyone is waiting for naturalization interview so no idea.
The field office was crowded today, the waiting area was probably at 80% of its capacity. I assumed I will be called at my appointment time but that's not the case. Everyone gets a number when checked in and they call us relatively in order, something like 50, 47, 53, 51, 55... I guess you might finish interview before your appointment time if you get there early.
I live in downtown Seattle and I never heard they assign applicants to Portland office.