I think that a balance shield would be an awesome spell! An example of when this would be useful, is with the O'Leary Burglars in Marleybone. I kept getting hit with balance spells and I had no shield to protect myself with! Besides, they have a trap, blade and shield for every school except balance. It only has a blade. A Balace Trap and a Balance Shield would be very useful, and it would go perfectly with the Balance Blade.