One of the greatest moments I enjoyed In Justice League Unlimited was seeing the Legion of Doom team up with the Justice League to stop Darkseid. Loved the conflict and antagonism, but seeing Superman and Lex Luthor teaming together (Well I don't actually remember seeing them fight side by side, but it was the whole league with the Legion of Doom) but it was fun to watch. That finale was epic and had arguably Superman's greatest moments in the past two decades, when Superman showed his true power and mega smacked the %&#@ out of Darkseid.
Would like to see that eventually. Obviously it can't be the exact story. Then again, Injustice is similar to the Crime Syndicate of America with Ultraman, and the Justice League animated series did the 'Justice Lords'.
Well Gunn's Superman is no doubt, Bizarro in disguise, but I hope to see a Justice League story (better to be a sequel) where the Justice League meets their doppelgangers on a parallel earth where they're dictators. Maybe not purposely evil, but a world where Superman cut loose. Seeing the Justice League face off their doppelgangers would be exciting. The third movie should be teaming up with Legion of Doom and battling Darkseid.
So with the title 'Man of Tomorrow', Gun seems to make it sound like which character earns that award. Sounds interesting. Don't see Lex could even stand a chance of earning that. Superman is the man of tomorrow obviously, so it couldn't be Lex.