This is pretty much what I do. I set up each ui to do certain similar actions on key presses. For example, = is my buff button, - is drink, 2 is cast Lightning Bolt/Fireball/Starfire/Holy Fire and was until recently blank on my Paladin. I set up a second action bar using alt-(1 through =) and typicially I only put things up there of a healing nature, such as specific macros targeting diffent character for a greater heal.