The Crimes Syndicate, the fairly little known evil Justice League from a different Earth, I think would make compelling villains for a future Justice League movie. DC is trying desperately to outshine Marvel, and doing something like casting an entirely different (and evil) Justice League could do that. These characters are different enough to need different actors, and I for one would kill to see two different Justice Leagues on screen. So, who could play this secondary Justice League? Let's find out!
1. Ultraman: Jared Padalecki
The evil version of Superman, Jared Padalecki is certainly qualified enough to play this role. Opposite Cavill, Padalecki has the same body stature, and is actually a little taller, as well as just as muscular. I think that Padalecki has what it takes to bring a more tortured and evil rendition of Superman on screen as Ultraman, and I would love to see him leading the charge against the Justice League.
2. Owlman: Zachary Quinto
Opposite Ben Affleck's extremely muscular and brutish Batman, Owlman is supposed to be more sly and cunning. Zachary Quinto is perfect for that. He has the perfect skinnier build for the role, and he's used to playing charismatic and deceptive characters.
3. Superwoman: Gemma Arterton
Compared to Gal Gadot as Wonder Woman, Gemma Arterton's Superwoman should be almost exactly the same. That's why she's my choice, because she was my favorite to play Wonder Woman. The characters are almost identical, especially since Superwoman isn't entirely evil. She's usually the one who ends up aiding the Justice League because of Ultraman's rejection of her and his delving into sheer evilness; that, and I think Arterton could perfectly exemplify this quality.
4. Johnny Quick: Liam Hemsworth
Johnny Quick is the fast talking, blonde, Australian counterpart of The Flash, and Liam Hemsworth fits the bill almost too perfectly. Despite being bulkier than Ezra Miller, he has everything qualified for Johnny Quick, and would be the best possible actor to play the character.
5. Power Ring: Bradley Cooper
We don't even know who will be playing the real Hal Jordan yet, but Cooper has what it takes to play the real Green Lantern, just as well as the evil one. Cooper has perfectly exemplified how he can go from charming to damaged in the drop of a pen in Limitless, and he's such a ranged actor that I have no doubt he could play an evil character just as well as a good one.
6. Sea King: Joe Manganiello
The hardest character on this list to cast was probably Sea King, because there are only a few actors that can match up to the size and dark look of Jason Momoa's Aquaman. Manganiello certainly meets both requirements. He's actually taller than Momoa (who is 6'4", whereas Joe is 6'5"), and as you can see he is super built. He's experienced at playing darker characters and has the same Aquaman look as Momoa. I'm certain Manganiello could bring the same presence to the screen as Sea King.
7. Grid: Ving Rhames
Ving Rhames is a little too old to play the evil version of Cyborg, I realize that, but I think that Grid would be better as CGI. Rhames has the perfect deep and menacing voice to provide this villain with, and some good old fashioned CGI could bring the actual character to life, with Ray Fisher doing the motion capture of course!