I have to agree with this. But in (virtual) reality, text bubbles would just and more clutter. But i totally see your side on this. Its much easier to keep your eyes on the battlefield as opposed to darting back and forth between that and the chat window. Its for that reason all my dots have a /ecoh sound effect tied to yhem.
95% of the time, healer/tank will add a sound effect into their more important macros to better allert people on what their doing.