too short?

I liked this movie, but it was so short that the pacing kind of confused me throughout. Sometimes they make movies short for kids, but this is hardly a kids' movie anyway. Surely, they could have expanded their world, and their narrative enough to add 30 minutes or so of action to the film? There are plenty of unanswered questions, unexplored possibilities, etc... I feel that there is something kind of ambitious about the premise of this movie, which deserved a substantially larger, more epic scope.