Or maybe it's just the problem of only having half the story...

There's that, too. (There's at least one bit in the film that a lot of people think could/should have been trimmed, that the writers have gone on record saying that it was necessary to set up something in the next film. Which is fair, but only up to a point: it may be necessary to the story as a whole, but it still damages this film as a film in itself. And I reckon they could have found a less obtrusive way of setting it up if they'd tried.)