Near the beginning, Plato tells his daughter that his friend Sam is shipping out for Kuwait the next day. However, the movie seems to forget this, as Sam never leaves for Kuwait, and is in fact an integral part of the film.
Throughout the film they'll be a random dragonfly that continues to show up. Granted, this happens in the swampyland section of the film, but it is cool. The dragonfly first shows up when Plato's swampboat runs aground and grenades are thrown at it from a heli. As everything explodes, pause or slow-mo the film to see a beautiful dragonfly race across the film. Later on, when the German Shepard runs to Plato and his daughter at the end of the film, notice how the dragonfly makes its cameo again. It is almost artistic and almost seems intentional.