Since Green Lantern has been ruined for an age in both comics and movies by the ineptitude of Geoff Johns, I'd leave that property out for at least 10 years. I'd establish movies of Superman, Wonder Woman, Batman (batman already has been established by Nolan), The Flash, Cyborg, The Atom and maybe Zatanna. Then maybe a Justice League movie would be do-able. Of course, you'd either need to steal Joss Whedon from Marvel OR find someone just as talented to direct the movies. The other thing I'd do is recruit the screenwriters from the comics themselves: Grant Morrison, Scott Snyder, Jeff Lemire and Warren Ellis. These writers know what make great comic book stories. (not the awful ones that Bob Harras likes).