Sorry that this is an old thread....is it okay to drag the antiques out again for some fresh words?
Anyway, I just wanted to add a suggestion that I've found helpful in interviews: When asked about the quality you most need improvement on (which some schools will ask), it's effective to say that sometimes your best qualities can also become your worst ones. It shows a richness of personality, and exhibits how you can have strengths and faults in all aspects of your life and are constantly working between the two.
Random examples: If your best quality is that you're proactive, motivated, and goal-oriented, your worst quality might be that you dominate relationships or conversations, aren't too spontaneous (i.e. you'd rather plan things out), or that you have trouble relaxing
If your best quality is that you have excellent interpersonal skills and are a great listener with lots of compassion and empathy, your worst habits might be that you are passive in conversations, you sometimes avoid conflict even if it's important, etc. etc.
I mean, if you're amazing at something it probably means that you're somewhat extreme about it. There's always a downside to it!! I've used this once or twice in interviews and feel like I got a positive response from it.