Bruce Wayne/ Batman: Jeffrey Donovan

Clark Kent/ Superman: Henry Cavill

Diana Prince/ Wonder Woman: Taylor Cole

Hal Jordan/ Green Lantern: Ryan Reynolds

Barry Allen/ The Flash: Michael Rosenbaum

J'onn J'onzz/ The Martian Manhunter: Carl Lumbly

Arthur Curry/ Aquaman: Chris Hemsworth

Oliver Queen/ Green Arrow: Justin Hartley

That is my Justice League fan cast though I'm not 100% sure about the last two. Feel free to comment. No trolls!!