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Let's approach it this way. Ask yourself what is more important...quality or quantity. If you are restricted to a specific schedule then break the trip up into sections and decide what appeals to you the most. The drive between SF and Redding is a 4 hr. waste. But the coastal road (hwy 1) is so twisty it would break a snake's back. You could compromise by taking 101 out of SF to the Oregon coast. from there it will be nothing but one picture postcard after another and you will have to discipline yourself not to want to stop every 5 miles to take pictures or run on the beach (which are free in Oregon by the way unlike the CA beaches).
Or you could go up I-5 and head over to the Oregon Coast at Florence and then up to Astoria with the same problem with too much gorgeous scenery.
So, if you have never been to the west coast, you need to experience the coast and not the interior which you can get just about anywhere.
As for the driving on the coast, that too is relative. It is not as scary as driving the Adriatic coast of Croatia but not as bland as East Texas. You will do fine.