I believe that both arguments are perfectly valid to explain why God created an ecosystem with predation. If someone does not appreciate the amazing creation of God, then I would like to see them create a universe which is better than the one we live in. Death is not evil. Suffering is not evil. Murder is evil and causing suffering out of malice is evil, but death is natural, and suffering is a natural part of life. If it were not for predation, then both the predator and prey would decline over time. Evolution causes the prey to run faster, the predator to see better, the plant to protect itself with barbs and poisons. None of these are evil!!! Death is as natural as life. Again, if you or anyone else can design a world in which all plants and animals are immortal, then I say go for it. If anyone can make a better universe than the one God made (They will not be able to, of course), then you earn the right to criticize the universe created by God. You say that God could create an ecosystem that does not need predation. OK, please find a biologist who would agree with you. You will not be able to, as this idea is nonsense. There is nothing evil about death. Humans die. That is not evil. Dogs die, fish die, trees die. There is nothing evil about this at all. What is the moral imperative of immortality? Pain is not evil. Pain is required to remain alive. Pain is necessary to life. Like I already said, if someone would like to propose a better universe, please go ahead, but do not just propose the idea, propose an actual set of laws and balancing forces which works, and then have to power to create such a universe. I believe you will not be able to improve on the one God created. But even if you could, I believe you would not have the power to create such a universe.
I agree that torturing a cat is evil. The Bible, specifically in the dietary laws in the Old Testament, opposes animal cruelty. Murder is evil. The Bible condemns the taking of human life for selfish purposes. Purposefully causing pain and suffering is obviously evil. But it is simply false to say that suffering due to natural causes is evil. Does it cause us to feel emotional pain when we see a lion kill an antelope? Yes, but this is not evil! I am not sure if God loves dogs. Maybe. He loves humans for sure, and he did not create them to be immortal. Death and suffering of humans is not evil.