In June, we will be at CoasterCon back east, and have 2 over filled days (opens early and stays open late for us) at Six Flags America, Busch Gardens Williamsburg, and Kings Dominion. Now we do get special entertainment and behind the scenes tours, plus things like a Midway Games competition, Rubber Duckie Race, etc. And due to the fact they all have so many great Roller Coasters (E-ticket rides), they can pull off the multi-day experience. And since it is a primarily adult event, we won't be spending much time in the kids zone.
Add 5 more parks before and after CoasterCon, including a multiple day trip to Carowinds. (2 days in Ocean City, MD and a day in Monrovia.)
But I would still say DCA is a half-day park, with three thrill rides (IncrediCoaster, Goofy's Sky School and GOTG) and Soarin', used to be better in version 1.0, plus now so many true knockoffs (same ride system), has loss a lot of its luster. RSR is a good ride, but more of a dark ride than thrill ride.