I'm currently WAS-based (Logan Circle) and have been with UA for about 3 years at or just below 1K levels of flying.
You say you don't like to connect and prefer DCA--well, American's gonna have you connecting to ANY of those foreign destinations from DCA *OR* IAD, whereas UA can get you to most popular, reasonable-range international destinations with no stops from IAD.
I don't think AA can get you non-stop to CDG, MEX, YOW, YEG or NRT on your calendar from WAS, UA can.
You have a TON of LAX-WAS on your schedule--I think the new American is gonna serve that about 6x/day (2 of them from DCA after they rejigger their schedule and 4x from IAD...but verrryyy $$$ to do the DCA-LAX flight) vs like 10-12 options from IAD for UA.
And recent devaluation aside, MPlus is still pretty competitive with AAdvantage, I'd say, on all the other various bells and whistles of the program.