What your talking about with the hold both triggers idea I already do. If you are gaming on a PC with the controller you can get a program called xpadder. Use this to set one trigger as shift the other as control and assign all your buttons some value not used in the game or make space by unbinding keys not necessary. Then create a hotbar with the appropriate key bindings. I added 12 new slots this way especially since when you hold both triggers it no longer registers anything but the joy sticks so there is no in game interference.