The first one is when Xiahou Dun gets his eye shot out, rips the arrow out, and proceeds to continue the fight! Unfortunately, his eyepatch is applied immediately after the cutscene, and there's no indication of the rumor that he ate the eyeball.
In the cutscene after that same battle, Zhang Liao basically telling Lu Bu to stop being a pussy and accept death like a man — which is implied to be the reason that Cao Cao chose for Zhang Liao to live and Lu Bu to die.
Dian Wei's death counts as both awesome and a bit of a Tearjerker
Huang Gai setting the Wei ships ablaze is pretty damn awesome.
If a cutscene must be a crowning moment of awesome, then Jin's ending is the best way to end the game.
Even moreso, that cutscene takes the usual 'Liu Shan not grieving on Shu' scene and have Liu Shan make a good statement about people shouldn't be too bound on past tradition to achieve peace, a statement that Sima Zhao agreed on... and in turn... makes the grieving Shu officers cheer in joy and probably makes an in-universe Rescued from the Scrappy Heap for Liu Shan.
The battle of Chang Ban for both Zhao Yun and Zhang Fei, the former for single handedly saving Liu Bei's infant son and the latter for pulling a You Shall Not Pass and to make his point he roars at them scaring the crap of most of them.
Guan Yu curd stomp Hua Xiong at Si Shui Gate.
Dynasty Warriors 7: Empires has a Skirmish mission where you get to drive a juggernaut. Sure, it's slow, but it's close to invincible, and pressing Circle shoots out jets of flame in a 270-degree circle around you. Drive it into a thick crowd of enemies, park flush against a wall facing it, and just press Circle every four seconds or so, maniacal laughter optional.