It might be a good idea to put six sided star gcd to its own really. Retain it's potency, raised cooldown to base 10s but now it is independent of basic rotations gcd. (Something like mch drill)

And yes tornado kick should be upgraded.

If we have greased lightning make every element 4 GL special effects: wind to reduce gcd by further 10% (total 50%), earth to ignore positionals completely, and fire to increase chakhra by one after each 3rd form rotations.

But by that above riddle of earth and some positional skills will be invalid so maybe earth should have other effects, knock back immunity maybe?