General opinion is to start at the park that doesn't have early entry when you don't have it. Though with DCA, it's only Disney resort guests, so it's not as much of an early crowd as you'll find at DL. But you're still arriving in the park with folks already in lines and pulling FastPasses.
As Stewart136 said, I'd say to either do your Plaza Inn breakfast later in the morning, or not on your Magic Morning day so you can maximize those morning hours. Even with regular rope drop, arriving as early as you're willing will pay off later in the day. Lines are much shorter in the morning, early entry or not.
If you're planning to ride GoTG, get in line or get a FP right away. Next, grab your RSR FP. TSMM FPs are much easier to come by, and seem to have a much shorter window for riding after you pull (whereas you may need to wait a bit for your GoTG or RSR FP window).
Have fun and happy planning!