Mirrors have been a core feature in ballet studios for over five hundred years. While physical mirrors provide real-time feedback, they do not inform dancers of their errors. Thus, technologies such as motion tracking have been used to augment what a physical mirror can provide. Current augmented mirrors, however, only implement one mode of communication, usually visual, and do not provide a holistic feedback to dancers that includes all the feedback elements commonly used in ballet classes. We conducted a mixed-method study with 16 novices and 16 expert dancers in which we compared two different modes of communication (visual and verbal), two different types of feedback (value and corrective) and two levels of guidance (mirror, or no mirror). Participants' ballet technique scores were evaluated by a remote teacher on eight ballet combinations (tendue, adagio, pirouette, saute, plié, degage, frappe and battement tendue). We report quantitative and qualitative results that show how the level of guidance, mode of communication, and type of feedback, needs to be tuned in different ways for novices and experts.