I don't necessarily disagree with the idea of Amaterasu as a warrior, (she has a sword after all) it just leaves kind of a bad taste in my mouth. I always thought of her based on her representation in Ukiyo-e paintings as a Mage who might use her sword for defense as opposed to attack. Her entire persona is defense based. She hides in a cave from Susanoo. She hates unnecessary death, like Uke-Mochi's, and warrior flies in the face of this. Also, while the Yasakani no Magatama was possibly Jade, the idea of the item specifically was developed in the Yayoi Period, a time where these items were much more often made from heated glass. Not only that, a preoccupation with Jade is more of a Chinese thing than a Japanese thing. Once Magatama started being made out of Jade, they went out of style pretty quickly. Making her ultimate Jade related sends the message that it's central to her lore, when the Yasakani no Magatama is more important in her great grandson's story than her's. Plus, Jade doesn't hold even remotely close to as much importance in Japan as it does in China. While it is symbolic of nature and fertility still, it's just not such a cultural icon, and doesn't represent anything Amaterasu is about. A better passive would be something involving the mirror, or painting as she painted the mountains and rivers onto the islands of Japan. Or perhaps something involving an eclipse, as that's what her main story is about. Perhaps the ult could be some sort of representation of her showing her full brilliance, akin to coming out of the cave. Also, while the wolf idea is cool, it's not even slightly part of her lore. It's only in Okami, and while that's a cool game, it's not particularly accurate in that regard as to representation. She is generally depicted in a white robe with red highlights and gold around her. I don't know how to make all of her lore fit into her abilities were she to be a Mage, but Warrior seems not quite right to me.