It is possible to save cpu by creating more presets with different effect combinations. But i like to have everything in one or two presets. More presets means more programming levelling and maintaining these presets after every major firmware update. Plus in this case you have to remember which effects are in which presets. You have to really plan and prepare your effects exactly how you will use them. That is something im not crazy about. I am more spontaneous type person. And you would also have to program your midi controller to have the same ias as your preset. And what if you want an effect that you havent programmed to your axe fx and controller? You would need to program both, and it is not something you want to do when you are at rehearsal or soundcheck when your band leader says 'hey this part of a song could use some ring mod.
I think it should be much simpler with fx8 going to axe fx front. I would control axe fx with small LF Mini controller, and i would control my effects with fx8.
That is my justification for wanting FX8