Our coast is pretty darn spectacular. That sounds like a good plan. Lots of nice places to stop for lunch or dinner in Astoria and Newport.

As for the 5th... yeah, you would need to be on the road really early to make it up Mt. Hood that day. It can be done, but you'll be in the car all day. If you wanted to just drive out 84 into the gorge and see some waterfalls, that would be easy and you would still be in the general vicinity of the airport.