Celes Chere
"I'm a general, not some opera floozy!"
"Locke... Let me protect you for once..."
"You want to live in this world as it is? No? Then do something about it!"
Yeah, she was pretty much my video game idol growing up. She starts off tough on the outside but scared and unsure of herself on the inside. She'd basically given up her entire life by leaving the Empire. But even though her in-charge persona is just a facade masking her insecurity, she never lets this stop her from doing what she needs to do. She becomes a mentor to Terra while Terra's still grappling with her new identity, she saves the party at the Magitek Research facility, and when Gestahl offers her absolute power, she stabs Kefka in the goddamn stomach. And after getting off the island in the WoR, while everyone else is moping around, Celes is traveling across the planet to reunite the party for an assault on Kefka's tower. Girl handles her biz.
Who goes from getting beaten by guards for betraying the evil Empire to leading an attack to save the damn world? That's right. Celes. Motherfuckin. Chere.