Utopia only technically killed one person. Saeko, and even then, it was just like absorbing her life force, compared to Daguba who just lit people on fire, just by pointing at them. The carnage you see Daguba unleashes, the cars crashing into each other, the passengers in flames, people screaming it was terrible. Not to mention Daguba went straight for the Amadam, cracking it, leaving Godai bloody. Utopia didn't even come close to hurting Shotaro and Phillip the way Daguba did.
I did however liked how Utopia actually hurt people, and raised the stakes a bit more after Double and Accel's failed attempt to defeat him.