What follows is something that I have occasionally tweeted about, worked out as a full-length case.
In the midst of--let's not call it a 'creative renaissance'--the tremendous amount of money being poured into comic book movies, it has frequently been noted that there has never been a good movie about Superman. Perhaps the first two qualify, the ones made in the late 70s/early 80s, but none since. The recent attempts have all been relative commercial flops. The last film's attempt to make his story more interesting outraged fans by having Superman kill General Zod as its climax, after a long battle in which Superman shows an uncharacteristic disregard for the lives of innocent bystanders. People will say that the reason for the failure of these movies is that Superman is a boring character (e.g.), that having essentially limitless abilities means all challenges to his power are doomed to fail and essentially meaningless. No drama, no story.
The failure to make Superman into a compelling figure is a good sign of the general failure of imagination in the comic book renaissance, because, italics required: Superman is a heroic figure cast into America's exact position in the world, capable for doing whatever he wants, for all practical purposes, but also living with a moral code that places severe limitations on the use of that power. Superman's moral code serves as a critique of the powers that be in our world, who are prepared in certain circumstances to compromise their principles in the name of results. Precisely because he can do whatever he wants, Superman recognizes the fragility and importance of every human life; he will go to ridiculous and wholly gratuitous efforts to protect them. This is in direct contradistinction to every other comic book movie, where one Sacrificial Family Member or Love Interest comes to stand in for humanity as a whole. When 'ordinary people' are mentioned or considered, it's as a mass--in The Dark Knight, the great validation of common morality is about the behavior of people in a group; in Spider-Man, the New Yorkers who aid Spidey at a critical moment are just schmoes who could be anyone (and these masses will become mobs whenever narratively convenient).
The idea that comics take a certain dehumanization of the average person, that they approach a line of fascist worship of power for its own sake, has its definitive characterization in The Amazing Adventures of Kavalier and Clay. Not surprisingly, giving someone great power--or practically infinite power, or power that can be redefined according to the needs of the story--makes them into a vehicle for wish fulfillment. But the line between killing/injuring in general and killing only bad guys is an exceedingly thin one. Killing an enemy combatant in a legally declared war is a lot closer to killing someone because you can than choosing to do neither, and if there's any distinction at all, it is in the specifics of the moral code in play. The unwillingness to use any means to win, no matter how important the situation, is one of the things that allows us to identify the good people, if any. The unwillingness to use power just because they can, and because it would be more convenient, is one of the things that makes them good.
The counterpoint is Harry Potter, where the good guys are notable for putting themselves at a strategic and tactical disadvantage because they, in anything but the most exigent circumstances, refuse to make use of the most powerful spells, because they value the humanity of individual human persons, do not like threatening the lives or wellbeing of innocents, Muggle or not, and recognize the tremendous horror of violence as experienced in the loss of loved ones. Molly Weasley can use these spells, when her daughter's life is threatened. Snape can, when it is necessary for the eventual victory of the cause, and Harry can, when it is literally the only option. But death is represented as loss, and other losses matter, too: Snape, Sirius Black, Dumbledore, even Dobby--all of them are treated as real tragedies in their own right, apart from consequences, and there's something equally sad about the fate of Neville's parents, or Hermione's. Each of the losses matter, and each has weight.
It's hard to imagine a comic book universe in which the Malfoys are allowed to live, and are treated with dignity because underneath their evilness is real familial affection, which redeems them in the end (bad guys whose goodness is not just the eventual winning impulse but definitive); so also with Snape. It's easy to imagine the opposite of Snape--the person who was good but goes to evil--but not the bad, or lost or misguided person, who is redeemed. This is also because his final redemption is in his death, which means he has to die in a definitive and irreversible way, which is Not Permitted in comic book and serialized fantasy/science fiction these days.*
*Contrast with Mystique in X-Men, whose small moments of redemption can only ever be temporary, because her role is "person who might be good or bad, we don't know" and is perpetually thus.