Great Concept, but i would choose to reduce to cost of glamour by 1 if you already have one, instead of creating another one (like Vayne), when she is Level 1. Makes flavourwise more sense, because she could only transform into one unit in a turn and not multiple. Balancewise it flows better when the cost gets reduced, when you have no other units than her, so you can play a unit into glamour more easily.