In a themed environment, roller coasters don't need to be as literal of an experience as, say, dark rides. Hulk simulates the rage of the transformation. Dueling Dragons is a little more literal, but it works in the outdoor setting. SWO/BGT have been doing animal personification with their newest coasters, Manta and Cheetah Hunt, where guests experience what it is like to be a manta ray and a cheetah. Outdoor roller coasters get a pass in that respect. Not all coasters have to be inside of a building for good story.