4. No Star Power
Since Man of Steel will likely be the only film to which Justice League will be directly attached, Henry Cavill may be the first actor cast. Can you name three other movies he's been in? If you can without researching it, kudos to you because I can't. The aforementioned Ryan Reynolds may not be recast, and Christian Bale has stated that he would only star in another Batman role if Nolan was attached; and Nolan has made it clear he has told his Batman tale and he is finished with it. Conversely, four of The Avengers had solo films (Iron Man, Captain American, Hulk, and Thor) not only allowing audiences to become more familiar with the characters, but also the actors. The only actor replacement was Mark Ruffalo as Hulk, and the Hulk is the one character where it really doesn't matter who the actor is because he is all CGI when in "costume." With no audience familiarity with the characters as they would appear in a JLA film or the actors who portray them, audience buy-in becomes extremely difficult and will rely heavily on marketing. This lack of any real star power makes marketing the film difficult, but another marketing concern is...