For This Troper, the CMOH in Final Fantasy XII: Revenant Wings was when the group had been transported to the home of the Yarhi, the realm of Illusion, and everyone's looking for Vaan (who'd faded away) in The Neverwood. Even though Vaan's there (although transparent) everyone's left except Penelo, who speaks to Vaan, even though she thinks he isn't there.
Penelo: Vaan...can you hear me? I know you've got your doubts about Balthier, the Judge of Wings, the aegyl...well, everything, but you don't have to face those doubts alone. Ever since we met, you haven't done anything but get me in trouble. So if that's what you're worried about, don't. I'm used to it. I've never told you this, but sometimes, when we're flying, I get scared. But it never lasts, because I know you're with me. But without you...I could never fly.
Vayne: [wounded and dying] Venat! I have failed us both. I am no Dynast-King. You must find another. One who might realise your ambitions.
Venat: They are fulfilled beyond your knowing. The Cryst is sundered, Age of Stones complete. From the Undying Ones the world is freed. You shall not tread this path alone. Together we go. Come.
Vayne: Heh. Won't Cid be eager to learn what has happened here. History begins anew.
Vayne and Venat then merge together to fight (and probably die) together.
The 'moment' between Balthier and Fran at the top of the Pharos when Fran has been befuddled by the Mist after the Sun Cryst goes crazy. Fran implores Balthier to leave her behind, but Balthier refuses. Beautiful.
Fran: * lying in Balthier's arms* The Sun-Cryst bursts. You must run, as far as you can.
Balthier: Easy, Fran
Fran: * Reaches up to touch his cheek* Hadn't you best be off? That's what a sky pirate does, you fly, don't you?
Balthier: * Takes Fran's hand, and smiles* I suppose you better hang on then.
The saddest/most heartwarming part is that 'hadn't you best be off?' was Cid, Balthier's father's last words to his son, before his death barely a minute before this moment. Balthier's expression says it all. In fact, Cid's remarks to his son as he dies are also prime heartwarming material. See the second half of this video.
Just before the last boss, when Venat basically tells Vayne: "I am proud of you, and I forsake my immortality this instant so you do not have to die alone."
At Jahara Ashe is contemplating what to do about the Nethicite when she sees Rasslers spirt again and runs towards it running into Vaan. For the first time ever the two have an honest to god talk about there fears, there pasts, and why Vaan decided to come along. He was frightened that he would begin to feel hollow and alone simply wallowing in self-pity as his talk of being a Sky Pirate was something he knew he honesty could never achieve and he used it to keep his mind off his brother. He then tells Ashe that he knows he'll find his purpose in life if he follows her leading Ashe to say "I wish I knew" but Vaan reaffirms that he'll find them. To many the scene may not be heartwarming but simply the two characters treating one another as equals when Ashe had previously treated Vaan like shit basically and Vaans complete trust in Ashe even when she is in doubt is something amazing
In the same vein ontop of the Pharos Vaan tells Ashe (interrupting her speech) that he knows she's going to destroy the nethicite, she responds back softly "Don't interrupt Vaan" doesn't seem like much? Don't interrupt had been Ashe's catchphrase for most of the early game usually said scathingly to Vaan or the other party members, and instead she sounds nostalgic, happy if a little bit sad. It highlighted just how far Ashe had come and how well these two now knew one another
There's a little one when you take the Wyvern Lord mark. The person who hires you turns out to be one of those good-for-nothing-Archadian-imperialist-scum-soldiers that have been occupying Rabanastre. However, the soldier hiring you explains that he saw the dragon while on patrol, but his peers and superiors thought that if it attacked the town, they'd take care of it then. The soldier, fearing for the civilian casualties that would result and believing them to be inevitable, pays out of his own pocket for the dragon to be put down. It soon becomes clear that this goes well beyond Even Evil Has Standards; he as a law enforcement officer cares for Rabanastre and it's people, and isn't just one of the generic Faceless Goons.