I do not often think it is a huge problem when Bong (or any similarly large-scale social commentary director) is either too obvious with his metaphors, or too heavy-handed with their presence in the continuity. But both!
Classic symptom of too many cooks overseeing too many Mickeys. Which, ironically, the film does seem to have a small, little acknowledgment of.
All of the humor stems from Pattinson over the script, a couple genuine guffaws when the edit plays himself. But the screenplay is, not for nothing, among Bong's most romantic. Will carry a lot of this movie's (... country's?) future than we can realize.