Pacific Coast has a surprisingly large number of hills on it, as you are often riding on tops of bluffs, not down near the shore. And every stream or creek that flows to the ocean cut a deep canyon that you descend into and climb out of.
Most of the hills I found to be 8 percent grade. But the alternate segments that the Oregon map recommends have a few hills in the 12 percent range.
My point is to get the gears you want for the uphills.
When you compare bike models that I am not familiar with, I can't comment on the bikes. But I can say if I was going to do that route again on a lightly loaded bike, it would likely have tire width from 32 to up to 37mm. I did it on 37mm tires, but was carrying camping gear.
Get the Oregon map for the part of that route that goes through Oregon. I found no comparable California map, but my information is now seven years old. Good info sources certainly could have changed in those seven years. I carried a California map with state parks, but I was camping.
Have a great trip.