JLA:JUSTICE LEAGUE OF AMERICA
SUPERMAN/CLARK KENT:HENRY CAVILL
Recently cast as the new Superman for a new generation I feel Henry Cavill will breathe new life and action into one of the most iconic heroes of all time.
BATMAN/BRUCE WAYNE:JON HAMM
Jon Hamm has been rumored for many comic book characters throughout the last decade. I think he is the next logical choice to take on the cape and cowl after Bale who will probably not be batman again since this batman is suppost to be a reinvention and more comic book stylized batman.
WONDER WOMAN:SERINDA SWAN
Serinda already has ties to the DC Universe having briefly played the role of Zatanna in Smallville; but this role should be cast as an un-known and Serinda is still in the category and would help to see Wonder Woman on screen instead of just a star powered actress.
THE FLASH/BARRY ALLEN: NEAL PATRICK HARRIS
Neal is "PERFECT" for the role of Barry Allen I think their is some discrimination against him because he's a gay actor. But if you have seen his voice work in JLA:NEW FRONTIER AND BATMAN UNDER THE RED HOOD then you know he can do justice to the role. Plus he has the right build and personality for the role.
GREEN LANTERN/KYLE RAYNER:MATT BOMER
Kyle Rayner is probably the most logical step to be the next Green Lantern on the big screen. Ryan Reynolds would not fit into a team up movie and will probably be killed of in Green Lantern 2. I think Bomer as Kyle Rayner would be a good backup Lantern.
AQUAMAN/ARTHUR CURRY:ARMIE HAMMER
Armie is a relative unknown and this film would do well with some unknown actor/actresses to fill out the ranks of the JLA. Aquaman is a part fitting for Hammer he would make controlling the minds of sea creatures look cool. In this he would be portrayed as the current version of Aquaman from the comics.
MARTIAN MAN-HUNTER:DOUG JONES
This part was made for Doug Jones he is a good performance actor when it comes to Mo-Cap and he would be a good detective Jones as well.
THE VILLAINS
DARKSEID:MICHAEL CLARKE DUNCAN
DUNCAN has an approachable yet intimidating presence on screen; Darkseid would be a role where he could lerk in the shadows until the climax of the film and then make himself known by taking on the entire league by himself.
GRANNY GOODNESS:KATHY BATES
Granny Goodness would be Kathy Bates in the film she would be Darkseids right hand "Woman" in the film overseeing his vast armies.
KALABAK:TIM CURRY
Kalabak would be the brute strength of Darkseids army and his main henchman; he would be done in mo-cap performance/voiced by Tim Curry.
LEX LUTHOR:MATTHEW GOODE
Lex Luthor would play a minor but pivotal role as he would be the first contact on Earth by Darkseid and even seen as a vessel for him from time to time throughout the film.
ORION:KEVIN McKIDD
I was originally going to cast him as Aquaman; however I think he would be better as Orion in a small cameo much like Jeremy Renner in Thor. McKidd would be seen at the beginning of the film as Orion coming to Earth to worn the JLA of the coming danger.