After posting my Superman, Batman, Green Lantern and Flash manips, I combined those pictures with new ones to create this:
The Cast:
Brandon Routh as Superman-He was perfect in "Superman Returns", no need to change him.
Sam Witwer as Batman-He can play dark, troubled characters, which is also great for villains, and he looks just like the comic version.
Victoria Hill as Wonder Woman-She almost definitely has the part and in my opinion, looks exactly like various versions of WW, including the JL cartoon and current comic books. She can do a perfect American accent too.
Geoff Stults as Hal Jordan/Green Lantern-DCUniverse suggested this pick and it is a great one. He looks exactly like Hal and sounds like what I picture Hal's voice to be.
Scott Porter as Wally West/Flash-He has the part and I'm not complaining. He looks just like JL cartoon/comic Wally and sounds like Michael Rosenbaum. He can play comedic and is a great actor.
Armie Hammer as Aquaman-I know how close he was to playing Batman but I prefer him for this role. He looks more like AC and he can play an authoritative role as well. I know AC is only 5'10" and Hammer is 6'5" but I actually want Aquaman to be taller than Superman (Routh and his character are only 6'3"). He's a good actor too.
Martian Manhunter is an Alex Ross painting.
So let me know what you think in the comments section.