10. Don't Cast Young Unknowns
The casting of unknown actors in their early to mid-twenties makes even less sense now than it did in 2007. These aren't new, inexperienced superheroes à la the Justice League of the New 52. These are seasoned champions that have already ushered in a time of "world peace." So a bunch of actors under 25 playing veterans would have been ridiculous, right? Even if the story had the heroes as rookies, a lot of the casting still seems shockingly bad. D.J. Cotrona, who showed absolutely no charisma or presence in G.I. Joe, would have made a terrible Superman. Likewise, the Australian model Meghan Gale was a poor choice for Wonder Woman. Her only role since the failure of Justice League: Mortal was in a minor Australian rom-com, suggesting that she didn't have the acting to chops to pull off one of the most iconic superheroes around. As an ensemble, the rumoured cast would have ruined what looked to be a really promising script. The actual Justice League movie needs actors that are already on their way to stardom. Think Henry Cavill or Christian Bale. Both had already proven themselves in smaller stuff before they took on their iconic roles.