Easily identifiable with hair flaps, different hair ornaments, and (most tellingly) a white sail on her rigging (a reference to how her crew rigged a white sail for emergency propulsion after being severely damaged in the Naval Battle of Guadalcanal). Personality-wise, slightly more aggressive and itching for a battle than her base form.
Her remodel greatly changes her appearance. Her hair becomes messier, with dog-like hair flaps and a red gradient, and she now wears a hairclip alongside with her ribbon. Her eyes are now red and her clothes become more ornate. It's implied she matures physically as well (this is partially confirmed in the anime), so many fan-artists draw her with far more notable breasts. Furthermore, her firepower's potential is practically on par with some of the heavy cruisers, making her very popular.