So I can see the story engine concept working very well for that immersive SW hotel experience.
I can't see it working in the theme park. Even if you limit guests...there are still going to be almost wall to wall people in the SW land. Think of how crowded some of the Disney lands (like Fantasyland) can get in the middle of the day on just regular sized crowd days. You can't have that super high level of immersive experience if all the cast members who are involved in the story have lines of 20+ people waiting to talk to them.
When I play a very immersive video game like World of Warcraft, I don't have to line up to talk to the quest giver. I just get to walk right up and interact.
Unless the story is driven entirely by your magic band or some element like a video screen that you are given, I just can't see it working like they want it to.
If it is like Universal's Harry Potter wand technology where you interact with the area and do spells, you'll still have to wait in line to use those elements. It won't be a fluid story experience, it will be a 'oooh this exciting thing happened let's rush to the next story element then wait 15 minutes and watch other people do it which ruins the surprise'.
Maybe I'm getting this entirely wrong and someone else can explain it to me. I just don't think this type of storytelling will work in the theme parks where you have massive amounts of people who want to 'play'. Though I do agree I can see it working in a very limited environment, like the proposed SW hotel.
I'm not arguing that the land won't be very immersive, I don't understand how they could do a highly interactive choose your own adventure type thing unless it is all just on a screen you are holding. If you have to interact with the cast members and elements around the land, I don't think it will work like it should.