Within your granted powers I would like to see how much it increases you and the drawbacks to using it. Inside both the manga and Anime the mask had fatigued Ichigo greatly and had a time limit at that.
So what exactly is your limitations as well as your drawbacks. How much does it augment your speed, power, and reiatsu. Also not all cero's are the same nor are all the gran rey ceros. detail those at lest two to five sentences.
At last is the shikai and bankai. Unless you are a Lt. or a Cap. you can not have bankai, along with that is the same thing as I said before, define it (what happens when you use it up, how much does it modify, etc.).