I will make one more comment on routing. As I mentioned before, I ended my southbound trip at San Francisco, thus I have no first hand experience south of there. A friend of mind did the entire route to the Mexico border with ACA as a van supported trip, thus ACA took care of all routing decisions, where to camp or stay in motels, etc. He said that the further south they got, the fewer campgrounds they used and more motels. I am not sure if it was the lack of campgrounds or if there was some other reason. My only point here is that you may find you need to plan for more indoor sleeping late in your trip.

If you are chomping at the bit, perhaps:
.

• you could go over your tools and spares kit, do you have everything you might need but minimal or no redundancies? (I have never needed more than one inner tube, but I always bring two, that redundancy is one that I will always carry.)
• one more review of your cooking kit, did you remember a cork screw if you might need one? If you bring a lighter along for the stove, make sure it is in your carry on, not checked bag. Etc.
• do you have the right kind of rain gear?

In the last few days before a trip, I will be sorting through gear trying to make sure that I cut out redundancies that I don't really need, etc.

There are lots of things you can fuss over besides the route.

I do not remember, when do you leave?