Captain Cold & Heatwave : James Roday and Dule Hill
Yes, I realize it's a gimmick. But for one, it's a gimmick that works, and two, maybe a gimmick or two is something the DCEU could use. Let's face it, Warner isn't exactly riding a high wave of fan confidence right now. Scoring the reunion of one of televisions most beloved comic duos of this century (Especially from a show whose fanbase largely overlaps with comic book fans) could bring in a lot of good will from fans cautious about Miller as Barry Allen, not to mention a ton of free press. It's not like reteaming a popular duo in these parts doesn't have precedence following their turn on the CW.
As for the actor/character combination itself, they certainly fit the bill: Roday as the cocky, smooth-talking Cold and Hill as his quiet yet explosive partner in crime, who would really love to get cured of his pyromania if Snart would stop dragging him into crime waves. Together, you get great chemistry at the heart of the world's greatest supervillain gang.
Weather Wizard: Ken Leung
I'll admit off the bat that Weather Wizard would probably have the smallest part out of the Rogues in my personal recipe for the film. But he'd certainly get to show off his powers and hopefully still be more memorable than the version from the CW. Ken Leung is a great character actor who can be both funny and intimidating, gelling perfectly in with the unavoidably likeable set of antagonists that are The Rogues.
Trickster : Will Poulter
I decided to keep Trickster as the kid of the group. The inherited mantle can still be used, but may prove to be unnesecary backstory. Not only does he give Barry a foe who is more of a peer, he also can utilize one of the best up-and-coming talents in Will Poulter, already well on his way to stardom. He can easily fit into the part of Trickster, who may annoy his older colleagues, yet proves vital with his technical expertise.
Golden Glider: Abigail Breslin
I cast Glider to be a peer of Miller's Flash, offering him a Femme Fatale, as well as making Mirror Master's affections for her one-sided, leading to conflict building for the film's climax. As with Trickster/Poulter, I selected a rising star with Abigail Breslin. She would slip well into Glider's quieter shoes, protecting her older brother who insists on keeping her out of the "family business" before secretly working with the Trickster to create her own identity as the Golden Glider.
Mirror Master : Morgan Spector
Combining bits of both iterations of the character, Sam Scudder/Mirror Master will be transformed throughout the movie from being little more than a getaway driver to Major Threat level as the Big Bad of the whole film. Already a bit unstable by the time COld & Heatwave break him out of prison, things only get worse. A poor relationship with his fellow Rogues, an unhealthy obsession with Lisa Snart, and the prodding of Cpt. Boomerang all result in delusions of grandeur which lead him to unleash his full capabilities, recruiting his own henchmen and taking dozens of high profile hostages within the Mirror Dimension, including Lisa. Morgan Spector is an accomplished character actor who makes one heck of a villain, and could do great things getting his big break in this part.
Cpt. Boomerang: Jai Courtney
Courtney makes his grand return to his splendid portrayal of Digger Harkness by doing what else? Join the Rogues. Secretly on assignment from Waller, he barges into Snart's fledgling team where he is less than welcome, having killed one of the team leader's friends on the job that got him captured. The ole' scumbag however is able to talk his way first onto the team, then into getting Trickster to deactivate his neck bomb. While he first proves a help to the team, his growing influence on Scudder proves to be dangerous for everyone involved.
The Recipe
-The Flash is a celebrity. As the movie begins, the inaugral Flash Day in Central City is being held. The high profile of Barry Allen's alter ego is a major point in the film, as is his friendship with fellow hero Vic Sage/Cyborg.
-Barry Allen is a detective. The CW show often fails to utilize Barry's day job, but it would come into the forefront here, as he tracks the Rogues and studies who their tech works. These investigations also bring him into contact with love interest, reporter and capable sleuth in her own right, Iris West.
-The Rogues are used as the central antagonists. While many might jump to using the Reverse Flash, that would fall into the cliche of the hero facing his "dark mirror", as well as repeating the all too commen mistake of utilizing a hero's nemesis in his first solo outing. As it sits, The Rogues have yet to be properly realized on the CW, giving yet another reason to make them the focus of the first film.
-The central plot focuses on Leonard Snart getting the bright idea to unite the Flash's past foes to utilize their individual strengths and become a "Flash-proof" gang, earning them all fame and fortune in the process. With his reluctant best friend "Heatwave" by his side, he breaks the other Rogues out of prison, and begrudgingly bringing in Cpt. Boomerang as the final member.
-The Flash is caught off guard as the Rogues begin their crime spree. Barry Allen and Iris West are both on the case. Barry's investigation leads him to Lisa Snart, who hits on him and manages to steer him in the wrong path. But as The Flash fails to stop the gang, his popularity wanes and Barry's confidence plummets.
-After getting some inspiration from Vic, Flash pieces the clues together and nearly beats the Rogues, they are only saved by Lisa's sudden debut of her Golden Glider persona. Cold is angry at his sister for disobeying him and putting herself in harm's way, but his leadership of the team, undermined by Boomerang, starts to crumble. When he finds out about Scudder's fascination with Lisa, he loses his cool, beating the Mirror Master and kicking him out.
-Scudder, egged on by Boomerang, recruits his own army of thugs and embarks on a crime spree filled with bombs, booby traps, and high profile kidnappings, bringing Central City to it's knees over night. Among the victims are Lisa Snart. The Flash races to stop Scudder's traps while the authorities struggle to negotiate with the increasingly unstable Mirror Master, who is starting to frighten even Boomerang. Cold and Heatwave come to Flash with vital information on stopping the villain, and the enemies begrudgingly team up to save Lisa and the other hostages.
-Together the trio enters the Mirror Dimension and defeat the Mirror Master and his minions. Lisa is safe, Boomerang gets shipped back to Waller, and Scudder is lost to the Mirror Dimension. In the end, The Flash is back on top of the world, Barry begins to date Iris, and Captain Cold, having learned his nemesis' secret identity, strikes his famous deal with The Flash.