In Orochimaru's view, Guren's Crystal Release was still very powerful once fully developed, but her personality was a bit too weak. Her vision was too narrow and her perspective too limited, which ultimately capped her achievements. Perhaps the women around Orochimaru were all like that; people like Anko and Guren simply lacked any real ambition. Anko just wanted to live a peaceful and steady life, while Guren's sole obsession was to become Orochimaru's reincarnation vessel. When she first laid eyes on the true form of the Three-Tails Isobu, she had been scared out of her wits—her performance was truly somewhat disappointing.
In contrast, look at Kimimaro, who possessed an unyielding conviction. Regardless of who the Jinchuriki might be, if his body hadn't failed him at the crucial moment, Gaara wouldn't have stood a chance. The Shinobi World is a grand stage—if you've got dreams, come on down! The law of the jungle dictates that the weak are meat and the strong eat; survival of the fittest has been the rule since ancient times. Since he had provided himself with such a clone ability, Orochimaru didn't mind nurturing her properly. How could such a great Kekkei Genkai fail to be used to its full potential? Crystal Release was roughly comparable to Ice Release, but its hardness was a step above. This aspect of the ability could be thoroughly developed, and as for countering sound waves, they could always figure out a way around it.
"There is no such thing as a perfect Kekkei …
Chapter 94