There was Captain America Vol. 1, #301 when Cap was still artificially aged as an eighty year old, seemingly doomed to remain that way. However, the Avengers try to change Cap back in a special treatment chamber when Mother Superior and the Sisters of Sin try to interfere and kill him inside. When the heroes finally enter the chamber themselves to save Cap, they find the Sisters reduced to toddlers, and, in a final splash panel, a youthful Steve Rogers standing grateful with Bernie, his full vitality restored for his new adventures to come as the renewed Sentinel of Liberty.
Cap's return in Reborn sees his reunion with Bucky, whom he hadn't had really got a chance to talk with ever since he was de-brainwashed.
Which soon enough, turns into a Moment of Awesome, with the two Captains America charging into battle.
And later, his exchange with Sharon. Few words, yet so much sweet.
God, you're beautiful.
Well, thanks, mister.
Cap and Fury meet up in Arlington cemetery. Cap notices the statue that erected in his memory back when he was dead.
Steve: They should take that thing down.
Fury: They should raise it higher.
In Captain America Volume 3, Issue 27, Nick Fury, by way of thanks and apology, comes over to Steve's place to give him a present - CDs of Steve's childhood favorite radio show, The Midnight Racer. The look of awed childlike pleasure and astonishment on his face at regaining a little bit of his life before that he thought was lost forever is both bittersweet and utterly heartwarming.
Towards the end of the first volume of New Avengers, Steve had just came back to life. Ms. Marvel didn't believe it was really him, so he whispered something to her at length. Cue glomp.
Cap's "American Reality" speech from Captain America #7 (Volume 3) is probably Cap at his speechifying best. The man just has a way with words.
The mere fact that Captain America is one of the few humans that Namor actually respects. Even if Steve doesn't like him anymore (understandably, considering what Namor's done in recent years), Namor still respects and supports him.
Cap: “You are not a freak! You are as good and decent a man as I’ve ever known! They can’t corrupt your love for Michael with their lies… They’re the disease!”
Shortly after the 9/11 attacks there was a throw-away scene in a story that was completely unrelated in which Captain America witnesses a horde of teenagers chasing an obviously Muslim man down the street, yelling epithets and making threats the entire time while the man protests that he was born in the US and is a patriotic citizen. Cap drops down between them and gently pushes the man behind him. And then he doesn't say a freaking word! The look on his face as he stares down these boys is enough to tell them, and people who act like them, that Captain America is very, very disappointed in them. It was enough to disperse the gang. And then Cap escorted the man home.
In the 'Castaway in Dimension Z' storyline, his whole interaction with Ian his adopted son.
During the Winter Soldier story line, Fury sends Falcon to Cap... because Steve needed a friend. And while Sam isn't initially keen on the idea of Bucky taking over as Captain America, by the end of his tenure, Bucky considers Sam his best friend.
Steve losing the super-serum looks like the last note of a long Trauma Conga Line, but it ends up being the point where things get better for him. He finds out shortly after that not only are Ian and Sharon both still alive, after he'd believed that Sharon killed Ian and then sacrificed herself, but they somehow found each other. When we last saw them, Sharon believed that Ian was some kind of mind control vision Zola inflicted on Steve. When we see them again, Ian reveals that Sharon raised him after Steve escaped Dimension Z and he calls her "Mom."
For a strange and very twisted version of Heartwarming, his encounter with The Punisher during Civil War. Cap assembles a mixture of heroes and villians to try and oppose the registration force...unfortunately, this includes the notoriously unstable Trigger Happy Punisher, who promptly kills two minor villains and gets decked by a furious Captain America. Cap proceeds to beat the Punisher black and blue, who just stands there and takes it even as the Captain has him pinned to a wall with his shield demanding to know why Punisher doesn't fight back. Turns out that the one person in the entire Marvel universe that Punisher refuses to fight is Captain America. He might be insane, disobedient, and violent to a fault, but he'd never lift a finger against Marvel's Big Good.
Captain America: Fight, you coward!
Punisher: Not against you.
During a darker story told in back of several issues of Captain America, some corrupt soldiers manage to drug Cap and keep him helpless to use as a bargaining chip should they need it (said soldiers were running from drug lords in South America about drug money owed to said drug lords). They come upon an isolated mission where the nuns are caring for the orphans that have resulted in the fighting. The mother superior is rightfully cautious of the soldiers (what with all the rampant guerrilla warfare going on) and telling them that they cannot enter the mission. When she sees Captain America, she states that only he may enter to be seen to about his apparent health issues (drugged). When asked why only Captain America can enter the mother superior tells them that in another country when a bus she was on filled with sick/malnourished refugees had broken down, Captain America found them by chance after a mission he completed. He ended up using his super soldiers muscles to pull all of them from the middle of nowhere to an inhabited settlement. To cap this off she adds another CMOH moment by saying:
It doesn't matter if Captain America is an American. He is a good man. A man of God.