It was recently rumored that Deathstroke will somehow be apart of the character lineup in David Ayer's Suicide Squad. While we still need more solid confirmation, the prospect does make a lot of sense all things considering. What makes me think Warner Bros. would want to include Deathstroke in Suicide Squad?
First-off, it was reported last year by BleedingCool that David Goyer was going to produce a bunch of DC Comics movies which included Suicide Squad and Deathstroke films. We don't know for sure if Goyer is still attached to either project, but it's very likely he was involved with the latter because he was going to write it. Deathstroke feels like a character that Goyer could really make a great script for, I don't think fans would complain about the body-count or gritty tone.
Second, Deathstroke is a current member of the new team in the comics. Harley Quinn only joined the ranks in 2011, but will be the female lead of the film. They could be including anyone slightly affiliated to group that are well known to fans. Warner Bros. might be looking for the most recognizable characters, since this isn't the original lineup from the Justin Marks script (Joker and Harley Quinn were never included in the original script). I'm sure Ayer's rewrites could see a couple of additions or swaps to the final character lineup (could Slade replace Rick Flagg?).
Third, the Marvel model for setting-up future films is a bit more Easter Egg-like, but having a character in the film before their solo adventure sounds about right for the DC Comics model. Remember, we'll see Wonder Woman, Aquaman and Cyborg in Batman v Superman: Dawn of Justice before they get their own movies. Deathstroke is still a relatively obscure character to general audiences, having him tag-along in Suicide Squad could definitely boost international awareness.
That said, what makes me believe that David Goyer would be or should be involved with this project?
Goyer is still in very good favor with Warner Bros., no matter what fans seem to think is going-on behind the scenes. He's still getting a writing and producing credits on Batman v Superman, even with Chris Terrio's rewrites to the original script (which I assume was apart of Affleck's contract, to have script approval). David is also writing-producing their NBC series Constantine and is involved with Joseph Gordon-Levitt's Sandman film writing the film's story. Godzilla's script had a rewrite from Goyer as well. It's possible that the Justice League script will include elements from the work Goyer contributed before Chris Terrio came onboard.
Last year he signed a three-year deal with the studio according to Deadline. The assumption that he would help godfather lesser known DC Comics film and TV properties for Warner Bros. It's led to him setting-up a Krypton prequel series at SyFy. His previous film development deals like Deathstroke would be alive and well, just not apart of the main release lineup.
Having written films like Blade and Dark Knight Trilogy/Man of Steel, Goyer understands all types of cinematic comic book worlds. Blade becoming the first Marvel success story, it's often forgotten the R-rated film was a hit two years before X-Men. Goyer is never credited for starting this genre, but he should. I could see Goyer doing for DC's Slade, what he did for Marvel's Blade. Turning him into a badass anti-hero, and one we might actually root for. Since, we've only seen him as a straight-up villain. Funny, since New Line Cinema (apart of Warner Bros.) was the home of Blade just until recently.
David also wrote the two Call of Duty: Black Ops games, two of the most successful games ever made. The first one selling 26.2 million copies and it's sequel earning over a billion within the first fifteen days. Those games show he has the chops to explore Slade's world of black ops soldiers and mercenaries. Sony announced him as writing their Metal Gear Solid adaptation, which has the director of Kong: Skull Island attached. Another intense military focused film which is another reason why Goyer staying-on as producer or writing the Deathstroke script might be a good idea.
What do you think? Should Warner Bros. pursue a Deathstroke film and keep David Goyer involved in some capacity?