In BLM's case, if even one thing happens that throws off your Ice or Fire stacks (Primal leaving screen, for example) a macro would only be a hinderance as you would be forced to restart your entire rotation from the top rather than making, say, one or two moves. I have aetherial manipulation macroed but that's pretty much it. For most of my buffs I have them on a shared hotbar that I access through R2+L2 iirc, with all of my offensive Cooldowns being on my main hotbar. (Ps3 user)