First off, the premise in itself seems broken. The United States experiences an inhuman entity that is posing a threat to the American people. So they’re solution to this problem is to hire people who had been locked in prison, and one crocodile man who lives in the sewer, for posing a threat to the American people.
Besides Diablo, who is basically the Human Torch from Fantactic Four, everyone else’s skills seem to include being psychologically unsound, having no allegiance to anyone, punching people, and the ability to shoot guns. The reason the government would contract these characters instead of the military in a supernatural situation such as this just vanishes. Like Captain Boomerang when given the chance to leave the mission (he later comes back with no motivation or reason to).
The intros the the characters make it feel like the screenwriter spent too much time introducing Harley Quinn and Deadshot, realized it was taking up too much time, and then gave each of the other characters like 30 seconds to show who they were.
We are given further details as to who these people are and why they are locked away in a scene that takes place over dinner between the Chief Intelligence Officer and another agent. We are then given the exact same speech about who these people are and why they were locked up in the next scene. In which she is debriefing her colleges on the plan to use criminals as superheros. There is also one character that has basically no introduction or backstory, as she is thrown in half way through the film. That character is Katana. I guess the idea was, “It would be cool to have a completely personality-less mystery women to help out in this battle.”
The Joker is one of the most disappointing parts of this entire movie. Jared Leto, the man who played him, had said that there was enough footage shot to make an entire film about him and Harley Quinn. What audiences got were just about enough snippets of that footage to keep him in as a character. He never really added to the main story line whatsoever, and half way through the movie the viewer is lead to believe he dies in a helicopter crash. (He later comes back from the dead to save Harley.) They also designed his charterer to have ridiculously on the nose tattoos. He’s damaged so they tattooed the word itself on his forehead. He hates Batman so they tattooed a bat symbol with a sword through it on his arm. This is the exact opposite of The Dark Knight. Where they took mass amounts of screen time to develop the character. This, to me, is just poor character development on a character that has previously been developed multiple times.
Finally, the color grading of this film is extremely dull. Shots have no color and seem muddy at most times. The majority of the film is done at night, in the dark, so that doesn’t help the look either. Unless they go into “Comic Book” mode. Which is like watching a Jackson Pollock painting and comes on abruptly to show how edgy the film is.
I could talk about the editing but all I have to say really is that the entire film was edited by a tailor house. People who are experts ate making things look cool but seem to have no idea what they are doing when cutting together full scenes, editing with continuity, and keeping any sort of flow in a film.