16. Alfie Allen Is A Magician... Let's Never Mention It Again
Because there are quite a few supporting characters, it's inevitable that some of them have to be sidelined in order to balance the whole story and focus on the right parts of the story. But because of that, we end up getting under-nourished story elements and some characters who do precisely nothing.
Take, for example, Alfie Allen, who appears as part of the troubled veterans team and initially seems interesting because he does magic tricks. It's like one of those flags in 1990s action movies that he will be important later, because they've bothered to give him a quirk. Sadly, that's about the only notable thing he does in the film - a card trick.
Likewise, the Man Of God cliche that is Augusto Aguilera's Nettles is entirely abandoned after its introduction, in favour of him being in love with Olivia Munn's Casey. Perhaps it's a conscious decision to make us expect them to be stereotypes only for those details to be entirely inconsequential (or merely a means to give them a personality where the rest of the writing fails).