If you have to look along the shaft of an arrow from the wrong end, if a man has you entirely at his mercy, then hope like hell that man is an evil man. Because the evil like power, power over people, and they want to see you in fear. They want you to know you're going to die. So they'll talk.They'll gloat. They'll watch you squirm. They'll put off the moment of murder like another man will put off a good cigar. So hope like hell your captor is an evil man. A good man will kill you with hardly a word.
The eponymous character of Lyrical Nanoha is one of the nicest people around and always tries to communicate with her enemies first. That does not mean she won't blast her opponents hard, if necessary, which may include students, friends or daughters. The fandom tends to refer to this behaviour as a kind of "Listen or be shot. Fail to listen, be shot again." mentality.
Dr. Kenzo Tenma from Monster is an excellent example. While a genius neurosurgeon, he's a humble, principled and compassionate doctor, loved by his patients. His only obvious flaw is his habit of manhandling those who offend his sense of justice. But when it becomes clear that he must go on a manhunt in order to save innocents from the monster he unwittingly unleashed on the world, he soon takes a level in Badass and becomes a fearsome vigilante.
Future Trunks from Dragon Ball Z is a Nice Guy that is very polite, and values life having come from a Bad Future where all the Z-Fighters have died. However, he's a Combat Pragmatist who is very serious in battle aiming to kill his opponents and even willing to fight his own allies if the situation calls for it. Such as when his father Vegeta wanted to aid Semi-Perfect Cell to become perfect. Trunks warns Vegeta that he will blast him to stop Cell but Vegeta thinks Trunks is too soft to shoot at his own father. Trunks proves Vegeta WRONG.
Luffy from One Piece. He's generally an oblivious person with a good heart, but has shown quite capable of taking on anyone, even his friends, if he feels they've done wrong.
Celty Sturluson is — underneath her fearsome reputation as the Headless Rider of Ikebukuro — easily the most sympathetic and benevolent figure in Durarara!!. Nonetheless, her fearsomeness is fully justified whenever she's dealing with lowly street thugs.
Superman, having Super Strength and all, tries to exert the least amount of force he can to resolve a situation. Occasionally, he will use a bit more, even to the point of hurting a villain more than he has to.
Spider-Man is an example in that he does want to help, being the Trope Namer for Comes Great Responsibility. That responsibility does not extend to his fighting style, which is fairly brutal. Some storylines revolve around him becoming more vicious, usually after donning the black suit.
Some members of the X-Men fall into this category, those who are firmly idealistic or genuinely want to do good also use their mutant powers to shoot Eye Beams or Mind Rape.
Film
Robocop follows three directives: serve the public trust, protect the innocent, uphold the law. Nothing is said about blowing away killers, or brutalizing a suspect before bringing them in.
Dirty Harry has no qualms about working outside the law or even torturing suspects, but he does try and lead a normal life.
Transformers: The Autobots are some of the nicest beings you'll meet, but they don't go easy on the Decepticons.
The movies themselves never established that powers were determined by alignment. A force choke is just localized telekinesis, after all, and the heroes are never shy about killing mooks.
Literature
Frodo Baggins in The Lord of the Rings. Sam begins to despair of Frodo's constant mercy toward the (in Sam's eyes) explicitly untrustworthy Gollum — until Frodo explicitly threatens to kill Gollum if he betrays them.
Sam looked at his master with approval, but also with surprise: there was a look on his face and a tone in his voice that he had not known before. It had always been a notion of his thatthe kindness of dear Mr. Frodo was of such a high degree that it must imply a fair measure of blindness.
Another Tolkien example in The Children of Húrin: when Túrin gets hospitality from his mother's kinswoman, the long-suffering Aerin, he tells her that she is a true friend but has a soft heart. Later, when the Easterlings attack her hall for revenge after Túrin has left, Aerin sets fire to the building and perishes with her enemies.
The Culture is a hedonistic post-scarcity society whose citizens mostly live to entertain, educate and enlighten themselves and their peers and spread their beneficial lifestyle to others, but at the edge of their ethics are apocalyptically powerful starships and agents who will do any kind of dirty business to protect and expand the Culture's interests, and anyone who tries to harm them learns a fatally hard lesson in why it was a bad idea.
"You might call them soft, because they're very reluctant to kill, and they might agree with you, but they're soft the way the ocean is soft, and, well; ask any sea captain how harmless and puny the ocean can be."
The page quote above comes from the Discworld novel Men at Arms. Later in the novel (and in other Discworld novels featuring the City Watch), recurring character Carrot Ironfoundersson proves that he fits the trope very well indeed.
The Knights of the Cross of The Dresden Files are modern-day paladins who will do their best to persuade Demonic Possession collaborators and victims to escape the thrall. If they refuse, though, the Knights have absolutely no compunction against killing them.
Live Action TV
Horatio Caine is genuinely caring of crime victims. He's not so pleasant with those who committed the crimes.
"You murdered thirteen people. You're a killer. You enjoy death. I hope you enjoy yours."
Compared to other Starfleet captains, Benjamin Sisko was quite willing to do things like poison a planet or participate in a murder conspiracy for the greater good.
Kamen Rider Amazon defeated his enemies not with fancy moves and cool weapons and kaboom endings to the fight, but by ripping the Monster of the Week apart with his bare claws and teeth and the serrated edges of his gloves. However, if you don't happen to be an evil monster, he's the nicest guy you'll ever meet. He's a Friend To All Children, Friend to All Living Things, and so forth. He once even saved a monster from being executed by his bosses for failing to defeat him! That monster became an ally for most of the rest of the series.
Doctor Who: From at least the Sylvester McCoy version onward, the Doctor himself is this. He's sent some bad guys to rather harsh endings to protect the innocent, has put good people in the line of fire or done otherwise unkind things as part of various gambits, and has had to make choices between bad and worse often. These things heavily weigh on him, but if it's between the destruction of Pompeii and letting the Pyroviles take the whole world, it often falls to him to throw the switch. This is thought of as a trait of the David Tennant Doctor, but just because that version had it explored the most deeply doesn't mean it hasn't been part of the series before and since.
One of the Doctors is explicitly described as this. The Ninth Doctor is a Good Is Not NiceJerkass who thinks he is better than everyone else. The Tenth Doctor is the complete opposite, fascinated by humanity and its foibles, genuinely caring and nice, and anyone who threatens them dies, no mercy, no second chances.
In the series four finale of Merlin, the sweet, gentle, friendly Merlin carefully and deliberately murders Arthur's Evil Uncle Agravaine in cold blood. Okay, Agravaine had just drawn a knife on him, but a) Merlin could have easily dealt with the knife without harming the man holding it, and b) Agravaine had just discovered Merlin's secret, and Colin Morgan's performance makes it very clear that Agravaine wasn't leaving that cave alive.
Religion and Mythology
In Norse Mythology, Thor is a Hot BloodedBoisterous Bruiser who spends most of his time drinking, eating and killing giants. Thor is humanity's best line of defense against the giants, who would otherwise destroy the world of men, and the stories told about Thor indicate that he truly does care for humanity.
The moment that perhaps cements this more than anything else in many fan's eyes is the ending to Overlord, where a scientist forced his autistic brother to communicate with the Geth, in the most barbaric way, then pleads with Shepard to allow it to continue. The bad option is to allow it but break his jaw and show disgust over his actions. The good one however is for Shepard to take David to refuge, dodge shots fired at him/her, optionally smash the scientist's face in and threaten to kill him.
"You even think about coming after your brother and this bullet will be waiting for you." Shepard threatens this at gunpoint, after the paragon choice.
Another example comes up in I Remember Me. If Shepard has the Colonist background s\he was attacked and nearly taken by Batarian slavers when s\he was sixteen. Because this becomes common knowledge Shepard is asked to talk to a girl who was taken by slavers and is Driven to Suicide. The paragon ending has Shepard save her, then the officer who asked for help despairs the point in fighting if they can't even keep little girl safe.
To make people who do things pay. It's not the severity of punishment that deters crime, it's the certainty.
The is one of the two times that Shepard, paragon Shepard, is absolutely furious.
A renegade Shepard, on the other hand, is a good demonstration of the sister trope, Good Is Not Nice, in that renegade Shepard can be a real Jerkass yet no matter how bad s\he can be Shepard is still trying to save the galaxy.
Turians in general, and Garrus in particular, show that not only are they incredibly polite and friendly, they're exceptionally ruthless and militaristic. Their combat philosophies directly reflect this: they hit the enemy with absolutely overwhelming force to end the fight as soon as possible.
In Lair of the Shadow Broker, the special Paragon solution to dealing with a hostage situation is to have Shepard do a Badass Boast calling out either the Paragon or Renegade choices for two of the most extreme actions in the previous game and saying that the hostage taker had better have a better plan than hoping a hostage will deter you. Although the intent was to intimidate the hostage taker into letting their guard down so Liara could free the hostage, there's a strong implication that if it had really come to that, Shepard wasn't bluffing.
A full list for just Shepard showing how Good Is Not Soft would take all day, but here's his\her reaction to criticism for sacrifices made to save the council.
Jun Kazama is The Chosen One and pure as the driven snow. This does not mean however she isn't devilishly effective in a fight, possess a series of powerful moves...brutal even, or in no shape to punch out Cthulhu. Or go all Mama Bear. Or as the latest game suggests go downright demonic in the pursuit of good.
Mariko "Spirit" Tanaka of Wing Commander is the nicest, kindest, gentlest creature in the series. Then she goes kamikaze on a Kilrathi held space station her fiancé is on.
Star Wars: Dark Forces Saga has Kyle Katarn, who through the course of the games was with the Empire, became a rebel, then a Jedi, fell to The Dark Side, gave up the Force, became a Jedi again for revenge, then began teaching others. His view of the Force and how to act is it's less about what you do, but how you do it. A good person for example can use bad means to achieve a good end, Good Is Not Soft in action.
Tellingly, Jedi Knight had a good and bad ending, dependent in part on what Force powers Kyle chooses. In Jedi Academy Luke will praise Jaden if s\he chooses light side powers or a mix, or become concerned if more dark powers are chosen.
Knights of the Old Republic uses this trope along with Incorruptible Pure Pureness. The backstory of the first game has the Jedi believing that good has to be soft, even with the Mandalorians running rampant. Revan, Malek, the Exile and others disagreed, believing that Good Is Not Soft and defied the order to save the galaxy.
As far as characters go, Bastila believes that a single misstep no matter how minor will doom a person, yet the likes of Carth or Mission believe Good Is Not Soft and are portrayed as being more light sided than Bastila.
Between the two games, it turns out that the Jedi Masters take their own stance on Good Is Not Soft. While they are happy to let the galaxy burn, they also Mind Rape Revan and attempt to strip the Exile of her force powers.
If you remain Light Side after defeating Bastila, she will express amazement that the Dark Side did not make her stronger, nor did the Light Side make you weak. This is foreshadowed by Juhani thinking the same thing. Malak will express the same, resigned revelation if you defeat him and offer to turn him back to the Light Side.
Kasumi of Dead or Alive is the nicest, kindest, gentlest character in the series (notice a trend?) She's also run off from her ninja clan and succeeded in not only finding her brother but killing the man who attacked him, while fending off constant assassination attempts, all while proclaiming she does not want to fight.
Kim Possible, a Disney character no less, is really caring and helpful, even more so as she matures. She has tried to reason with the villains at times, but most episode has her resorting to her fists to resolve problems.
This is a trait shared by many Autobots (and Maximals) throughout the Transformers franchise, both figuratively and literally. Optimus just tends to embody it best.
In the G1 cartoon, during a flashback to his first meeting with Megatron and being rebuilt into Optimus, there is a scene where he just blasts holes into 'con after 'con after 'con. In Transformers: The Movie, Optimus literally runs over one Decepticon and blasts several others before he confronts Megatron.
Alpha Trion qualifies for this as well, for rebuilding him. After all, he knew warriors would be needed, so when two of his friends were injured, he didn't just rebuild them as they were - he rebuilt them as Badass Decepticon-slayers. Imagine waking up in the hospital with an Arm Cannon in preparation for the next time you ran into the guy who put you there.
She also banished her beloved More than Mind Control affected sister to the moon for a thousand years, because she was trying to cause The Night That Never Ends which would've had omnicidal consequences and Celestia wasn't powerful enough to remove the corruption. That is firm leadership, ladies and gentlemen (though Celestia, by all appearances, didlose sleep over that decision).
