In my opinion I think all joints should be the same price. For example, 128 joints would be 11k, 256 would be 25k, and 512 would be 50k. You don't want to make the 128 overpowered tho. Since 20 x 11 = 220k. That means you now own ever force color except for Pure. So that's where the Qi restriction would come in. A minimum Qi of 8th - 10th dan should be required. That's just my opinion tho.