It wasn't that the Acacia Family Singularity Technique was so much better than the other two. It was only that in consideration of Dyon's circumstances, their technique happened to be perfect for him.
When Dyon had first met Ri, she had told him that her father's manifestation was mist. At first, Dyon had attached this to Uncle Acacia because he hadn't been aware of her origins at the time.
But, something was wrong. Did Ri mean that the King had a mist type manifestation? But, according to his knowledge, King Acacia was the first of the Acacia family to awaken their original manifestation in millennia. Yet, the Acacia family technique wasn't mist… It was a manifestation they called: The Tree of Life and Death.