Are you sure Washington State is that simple? I don't live there and only spent a few moments researching, but I don't see that WA has guaranteed issue with continuous coverage. It does seem to have guaranteed renewal, but that locks you into one insurer, doesn't it?
Here we have something called the Standard Health Questionnaire (SHQ), which they make you fill out when applying for insurance. But there are a bunch of exceptions at the top which make it possible to avoid submitting the SHQ. Running out of COBRA is one of those exceptions.
This is exactly how it worked for me when my COBRA coverage expired and I lived in WA. Bypassing the SHQ was key to getting reasonable rates for myself.