To be honest making locators to do a global scale isn't the proper way we do in the industry. Always remember joints bind to the geometry, controllers are constrained to manipulate the joints. All animators touch are the controllers themselves and thats it.

You will essentially have 3 main group nodes or containers. "MESH", "JOINTS", "CONTROLLERS". Each one has underneath what corresponds to it. After each joint that you want to be manipulated has its own controllers you then add a "PLC" which is short for placement controller, which basically is a nonkeyable controller that animators use to place a character, prop or vehicle in position in the scene.

This PLC controller as well has an attribute you make that connects to the Scale X,Y and Z of that same controller, that way animators just manipulate that controller's new attribute called "Global Scale" and they don't have to worry about it again. The PLC is in other words the "root" and main controller of your entire rig.

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