And here’s how we’ve traveled between cities.
SF to Monterey: we took the Coast Starlight from Oakland to Salinas, and then the Amtrak thruway to Monterey. (If you book Oakland or Emeryville to Monterey on Amtrak it includes the bus. You can also book a pickup from SF, but I don’t love that bus terminal)
Monterey to LA: a coworker drove us, in her pickup truck, on the 101. It was 6 hours of farmland. Truly shocking to see the vast space of central California sometimes. No matter how much I see it.
LA to Portland: we flew Alaska Air from Burbank. I’ve learned that Alaska + Burbank (instead of United + LAX) is the only way to have a decent and maybe even good flying experience. United and LAX are bad experiences all around.
Portland to Seattle: we are currently in the bus. I bought a ticket through Flixbus. The bus ended up being from another company (MTR western) but is decent. A little nicer than Greyhound. We are used to long distance buses / coaches anyway.