First off, congratulations on the milestone and for the very fun and challenging goal you’ve set! I was born and raised in Oregon and have some experience on the coast. That is going to be a gorgeous adventure!
In addition to the very good base layer recommendations offered here, my first thought was about rainwear. My current favorite is the Outdoor Research Interstellar jacket. It’s super light, waterproof, has a bit of stretch, and importantly is far more breathable than most. I’d also recommend a good set of poles. I can personally recommend Black Diamond Distance Z and Leki Micro Vario Carbon, but there are many good choices out there. Enjoy!