I disagree with the OP on a couple of the rides.
I don't think you can compare Space Mountains, because of the theming, it's almost as if they are two completely different rides. DLR has the better coaster, I think, and I love it. But WDW reminds me so much more of the "space race" and America's race for the Moon and all the potential that it held. Both are great, but for completely different reasons.
Soarin' at DCA makes much more sense. I grew up reading about the early pioneers of aviation, and California was a center of aviation innovation. It's queue (at least with the old film) and the revamped DCA theming was JUST RIGHT. I felt like I was observing The Right Stuff. Don't know how either theater will shake out with the new film.
And...I actually prefer DLR's HM and SM. It fits with the New Orleans Square, which I think is the best land in any of the American parks, and I like the audio-animatronics at the DLR Splash better. The ride makes more sense, thematically.