They are ALL copying someone. Look at Cook with his scarf and Syesha barefoot. Both have been done already this season. These kids are just trying different things to make their own statement (which just happens to have been done before.) Actually Jason is probably the most original of the group and doesn’t change his style for anything or anybody.
Brooke definitely knows where she belongs, but it took her a couple of whopping mistakes to realize that she wasn’t only uncomfortable out of her zone—she just couldn’t function there at all...BUT now she knows, that’s the beauty of this whole show—watching the kids discover who they are.
I read an article a while back. When she went barefoot and sang from atop the piano, it was because they didn't want to scratch the piano. Then I read that she doesn't like wearing heels, which might explain the bare feet.