I think a lot of the more serious superhero movies that want to explore in any depth the idea of the hero and its place in a more realistic world are going per force to tread on many of the same material as Watchmen. Alan Moore has stated that the hero, and the superhero in particular, can be a mostly toxic idea, a whitewashed glorification of the violence of individual glory-hounds or outright monsters. So if you want to do tackle those issues you have to address such perspectives. It all goes back to a common notional core of this particular conceptual debate.
Except Snyder doesn't have the ambivalent attitude towards violence that Moore does, and that's why his 'Watchmen' was such a hollow movie.
This is Moore's formulation:
Comedian: A sociopath and a remorseless right-wing creep, but genuinely disturbed by murder on macro scale.
Rorschach: A deluded Objectivist whose moral clarity is somewhat sympathetic, even though he is clearly crazy, smelly and scary. He started out with good intentions but his experience of human brutality has left him permanently deranged. While he is correct to be horrified at Viedt's actions, his moral absolutism may destroy the fragile peace that has been acheived at the end of the story.
Dan: A 'normal' person with conventional values, who nevertheless participates in covering up a mass murder for the sake of peace.
Laurie: Same as Dan.
Dr. Manhattan: A Superbeing whose powers have rendered him distant from human emotions and concerns of morality, who also agrees to cover up the massacre.
Adrian Viedt: Committed to stopping WWIII. Correctly sees that 'costumed heroes' are at best, tools of the corrupt establishment, and at worst, totally ineffectual perverts and sickos who are part of the problem. So he implements a plan may save the planet, but at a horrific cost.
Expanded cast of comic-book boy, news vendor, prison psychologist, etc: Normal people who we get to know and whose fate is essential to understanding the costs of violence.
Here is Zack Snyder's formulation:
Comedian: Creep who gets his in SUPER-AWESOME KUNG-FU FIGHT
Rorschach: Super-kewl GOOD GUY VIGILANTE who takes no guff, and knows how to take out the garbage. Also he's SUPER AWESOME AT KUNG FU
Dan: He's a superhero and he's ALSO GREAT AT KUNG FU, BRO HE JUST PUNCHED THAT GUY SO HARD HIS BONE POPPED OUT
Laurie: Just like Dan but SOOOOOO HOTTTTTT
Dr. Manhattan: SUPER-BUFF, HUGE PACKAGE, SUPER-POWERS, BRO
Adrian Viedt: BAD GUY.
Expanded cast of normal people: WHO CARES BRO. UNLESS THEY KNOW KUNG FU.