More for the writer than the character: At the end of a story that involved a female villain with female Mooks, a fellow Amazon didn't understand why those women would work for the villain. Wonder Woman explained that she didn't understand the women in "Man's World": Many of them wanted to be slaves, not having the courage to take control of their lives and compete with men. Keep in mind that a man wrote this. In the 1940s.
In the character's first Post Crisis storyline, Diana is fighting the progeny of Ares, Deimos, and is ensnared by his beard of snakes. Seeing her mortal friends being overwhelmed and she must save them, Diana shows a new big difference compared to her compatriots of The DCU, Batman and Superman. Namely, she doesn't feel bound by Thou Shall Not Kill and so takes the god's head off!
The return of Barbara Minerva as the Cheetah in Wonder Woman (vol. 2) #206, killing Sebastian Ballesteros and leaving a trap for Diana:
One comparatively low-key moment: Diana's coworker at the Taco Whiz (long story) has a daughter she can't afford to send to a prestigious school. The father is a deadbeat who also works for a mob boss. Diana gets the child support checks coming by camping out in the boss's office and answering his phone.
Hello, yes. This is Mr. Sazia's residence. I'm afraid he can't come to the phone right now. Me? I am Wonder Woman. And who might... hmm. They hung up.
During Greg Rucka's run, already full of awesome, one moment stands out: Diana faces Medusa in an arena match. The gorgon has already petrified the child of one of Diana's employees, so It's Personal. And it gets worse: Circe has enchanted TV systems across the world, and if Wonder Woman loses, tens of millions of people get turned to stone with her. Right as it looks as though she's about to lose, she takes one of Medusa's severed hair-snakes and blinds herself. Then she takes Medusa's head off with one slice.
Also from Greg Rucka's run, she gets Batman to surrender after a one-on-one fight.
In "Ends of the Earth", Wonder Woman started to lose her soul. So what does she do? She teams up with Beowulf to kill the freaking devil and takes it back.
The producers noted any time there was a huge fight, Wonder Woman was always the one kicking the most ass.
Up to Eleven when in one episode, she is being mind-controlled and takes on Black Canary, Huntress, Hawkgirl, and Vixen single-handedly. It's pretty one-sided (memorably, Vixen takes on the strength—and mass—of an elephant; Wonder Woman casually power-bombs her) until the signal that's controlling her stops her right before she bashes Vixen and Hawkgirl's heads together.