I think the 'design flaws' are proff that we didn't evolve. If we had evolved, we would have been better suited for life on this world. As far as 'design flaws' by God. God created man with perfect bodies in his own image. Our imperfect and mortal condition is because of the fall of Adam and Eve. Also the inbreeding of Adams children would have resulted in weaker genes. That's my opinion anyway.
Design flaws are excellent proof that we evolved. As we evolved, different body parts would neccessarily have had different functions, in that we had a different style of life and different needs. As we changed, through natural selection, it would be easily explained through evolutionary mechanics that what we had needed previously would be disregarded when we came up with a different arrangement, and what we had used before would be used in a different manner.
A simple example - we get goosebumps when we are frightened or are cold. This has no use for us now, but in the past, this would have raised the hair on us, making us appear larger, and more intimidating, when we are frightened. It would raise hair on us, and help us keep warm, when we are cold. Because we are not very hairy creatures now, goosebumps do not help us frighten animals, or keep us warm.
I can use the theory of evolution to explain goosebumps, but I cannot use Intelligent Design to explain why we have goosebumps.
Second point - evolution does not say that we have to be perfectly suited for this world. It says that we have to suit it enough merely so that we can breed, and pass on our genes to the next generation.
Evolution is a constant process, and because the world changes constantly, any standard of perfection cannot be attained. Sometimes there are droughts, or floods, or a famine. A new predator might arrive on the scene. Each circumstance will better suit some individuals over others.