I came across this thread by Judy doing a search for something totally different. But looked it over and though wow how things have changed in 7 years.
My three.
1. Rocking Roller Coaster, indoors could be squeezed into DCA, a fun coaster ok theming.
2. The Osborne Family Spectacular of Dancing Lights. For the most parts I think Holidays at WDW and DLR are the same, except for this. Right down Hollywood Boulevard. I know it's not a ride, but it's a great attraction.
3. Voyage of the Little Mermaid, not terribly popular, and not the ride coming to Paradise Peir. But I really like this stage show, lots of special effects, well designed. WDW has lots of big shows, if DLR had more than Aladdin I think it would be seen as so great.