I got around to watching the first episode and it was a nice adaptation of the early volume 1 events. Her interactions with Lynokis were everything I wanted, and the stunned silence after she cut with a wooden sword really brought that scene to life.
Reading through the English translation of the light novel, I had a more masculine impression of her, but Nia's precocious way of speaking feels a lot more feminine in Japanese. They came right out of the gate making her seem like total grandma with having candy at the ready, too.