SEA customs / immigration is a nightmare that could quite easily be fixed by implementing a slot system. Why have so many widebodies (8?) arrive in one hour, just around noon? Spread it out! Standing in the hallway in double lines for over an hour is not doing anybody any good. I've stood there, quite a few times.

As far as Boeing and loyalty to As or Seattle.... there is none! Headquarters moved to Chicago, training center to Miami, half of 787 to S. Carolina, part of design to Russia, 787 parts to all over the world. 777-X almost left but thanks to a subsidy from the taxpayers in a fight to keep jobs it stays in Everett. Trying to keep jobs so they can lay off 4000 people.
I would be very surprised if the next plane they come out with will be built in Seattle. Charleston, Alabama, China....
And a little fish like AS should be important when a Ryanair orders 200 737's at a time, or Emirates orders 100 777's? I am surprised there is not a 777 assembly plant in Dubai (DWC) yet. Plenty of space, plenty of cheap labor, and another biggest / first / only "thing" in Dubai. Aluminium plant next to the airport. Two of your biggest customers within 30 minutes flying. Quality control will be a big issue. The mentality of the cheap labor is that it does not matter if something fits correctly, if it kinda looks ok, then it is good enough.