With the way the game works now you wouldn't need to macro change hotbar. It already changes automatically with level sync, like your Stone button will be stone I, II, III or IV depending what level you're synced to. For SMN, ruin I and III share a button. Ruin II becomes ruin IV when it procs from a pet action. SCH's ruin, broil and broil II share a button, also dynamically changes based on your level.