If this were real life and the music industry, the gyaru chick would win the competition, since she's more marketable. She's like a pop star, Taylor Hilton or whatever. Makes tons of money with catchy yet shallow lyrics and colorful props at concerts. Oh, and her dad was also a country music singer.
Hibiki, on the other hand, would have her cathartic techno playing at anti-government protest raves in Tbilisi, with punters getting high and setting fire to stuff. The soundtrack of a revolution.