I realize this is a months-old post, but this is a pet peeve of mine:
Ignoring all other species and just focusing on humans: If we were the product of intelligent design we wouldn't have colds or pneumonia. The human respiratory system works great - if we walked on all fours like other mammals. Since we walk upright, fluids build up and drain down into the lungs, causing pneumonia. That's just one example of how the human body really isn't very well put together. A better design would have prevented respiratory problems. Any decent mechanical engineer could come up with dozens of ways to improve the human body, make it stronger, make it longer lasting, make it more resistant to disease and infection and damage. The idea that we're somehow the pinnacle of perfection just because we dominate the scene deliberately ignores our many shortcomings.