The Guardians of the Universe in Green Lantern used to be this, but Geoff Johns' more cynical take on them had them acting aloof and manipulative instead. This continued until they were killed off at the end of his run. The New Guardians are following a similar trajectory.
Superman is traditionally the chairman (and often acknowledged as the most powerful member) of the Justice League of America, and when not acting in his capacity as a Leaguer most other heroes tend to defer to his authority and judgment if only out of respect. Sometimes generalized to the "Big Three" where Superman, Batman, and Wonder Woman collectively comprise the Big Good of the JLA. (The JLA itself is in a sense the Big Good of DCU superteams and/or the metahuman community in general.) Explicitly shown in the Trinity maxi-series, to the point where the three become gods.
Despite being curmudgeonly, brooding and feared by almost everyone, Batman, Superman and Wonder Woman tend to share this role in the larger DC Universe.
After attempting to uphold Batman's legend, Gordon is saved and assisted by Batcom, an A.I. designed by Bruce Wayne.
Superman & Batman: Generations: After Ra's al-Ghul's death, Bruce Wayne takes over his organization and turns it good, simply by turning the "front" organizations legit so subtly that most of Ra's' staff assume it's part of a larger plan until it's too late. He passes it on to Bruce Jr. so he can go back to being Batman.
In a similar capacity, Captain Marvel is often treated like this, even in comparison to Superman, possibly due to Children Are Innocent. It's explicitly stated in the comics that Billy Batson would be Marvel full-time to help people, if not for the wizard Shazam insisting that Batson himself deserves some happiness in his life, too.
Darkseid's opposite in the New Gods mythos, Izaya, Leader of New Genesis, is supposed to be the Big Good of the Fourth World saga - but he hardly ever gets used, to give the spotlight to characters like Orion, or even Earth heroes like Superman. Highfather is more or less purely defensive/reactive, which makes him kind of boring when compared to the more active New Gods like Orion or even Lightray; he's mentioned a lot more than he's shown. Also referenced-but-not-shown is The Source. The Source Wall has been shown in the comics, which is presented as a kind of barrier around the universe, composed of the frozen-into-stone bodies of beings who dared to try to venture past it.
"Wonder Woman": When the gods were included in the Golden Age, huge liberties were taken, with them often ruling over the planets named after them, but Aphrodite was the Big Good to the Amazons as the goddess of love.
"Wonder Woman": As Diana's main patron and the first God to forgive the Amazonians and give them the strength to free themselves from imprisonment. As long as they forgive their captors, Athena is this.
Jor-El is Krypton's greatest scientist, as well as the father and mentor of Kal-El (who would later named Superman). He sent his son to Earth along with the Codex so Kal could re-build Krypton's civilization with humans and Kryptonians coexisting peacefully, counterbalancing Zod's intentions to re-build the long-dead Krypton by wiping the humans out.
Superman himself intends to fulfill this role after Jor-El told him that his destiny was to become this for humanity, and he works hard to reach this point in both Man of Steel and Batman v Superman: Dawn of Justice. Even while he's believed to be dead, his example still inspires Batman and the rest of the Justice League.
In Aquaman, Atlanna had a heavy influence throughout the movie. She conceived Arthur with Thomas Curry, then birthed Orm and mentored Mera. When she was presumed dead, it shakes everyone who knew her, though Thomas still won't give up on her. When Atlanna shows up well and alive, she manages to convince Arthur to take his place on the throne of Atlantis and stops Orm from recklessly throwing his life away.
SHAZAM! & Fury of the Gods: Wizard Shazam was already a major benevolent figure in the first film, but this was undercut by his character flaws which unwittingly caused the main conflict. In the sequel, however, he becomes a straighter example, as he alerts Billy to the presence of a new danger and encourages Billy when he starts doubting himself.
The Batman: Batman himself takes up the position after he realizes that his quest for vengeance was only making things worse for the people and inspiring criminals like Riddler to endanger them. To mend this, he steps into the light at the end of the film and decides to guide Gotham back from the brink as a symbol of hope rather than fear.
Live-Action TV
The trope is Played With in the case of James "Jim" Gordon from Gotham. He becomes Captain of Gotham Central early in season 4, but it's only because Sofia Falcone needed a puppet and blackmailed him by making him complicit in her crimes, and Bullock later convinces him that while he might not feel this way about himself, the GCPD believes in him as such and he needs to project that image. In season 5, he's the only high-ranking official left in Gotham, and takes hundreds of refugees under his protection with the remnants of the GCPD - albeit with pressure he's under and bad decisions that result, especially after Haven is blown up.
Smallville: Clark Kent intends to fulfill the role by becoming the Earth's greatest savior known as Superman.
Video Games
The Batman: Arkham video game series give us the titular superhero himself, who fulfills this role as the leader of the Batfamily and Gotham City’s protector.
Gotham Knights: Like in the comics, Batman is the number one enemy to criminals and a major deterrent to crime.
In the first game, the main universe’s Justice League Superman takes over the role once he's brought in by the Insurgency, since he's the one to finally stop his Regime counterpart.
The Insurgency Batman also takes up the role, as he is leading the resistance to stop Superman's reign of terror. Later he leads the last remaining heroes left that refused to cross the line and is the only person everyone else looks up to.
However, Superman takes the reins of the show. Several heroes have admitted that they looked up to him. His "death" in Hereafter presents a huge loss and concern to the Justice League's future heroics. The Flash admitted he didn't always have to worry about the situation with Superman around, and Batman showed his respect admitting he learned from Superman that justice didn't always have to come from the shadows.
Once again, the Justice League serve the position itself in Young Justice, which the characters frequently mention as possible support when it looks like the situation is something they can not handle themselves. The League also has a rotating chairman who embodies the trope more than others. Batman's the League Chairman in Season One, and while he may seem (and sometimes is) hard and strict on the team, he ultimately praises them and encourages them to work together. Captain Atom becomes the League Chairman in Season Two, and Black Canary is made the Chairman in the series finale.
