"My argument is based on the nature of good and evil, not humanity. Opposites need each other. Up and down, justice and injustice, hot and cold, good and evil. A chemist might tell you that in reality cold does not exist--it's merely the lack of heat. I would say that good and evil work the same way."
None of that answered why we're programmed to need it to work this way. The cold/heat analogy is flawed because heat is an observable physical phenomenon (and cold is 'observable' by proxy -- as a relative absence of heat). You can't take a thermometer or equivalent instrument and determine an object's "good" or "bad"; the analogy is painfully pseudoscientific. What you said earlier is that humans understand evil as the absence of good, and that's why they need each other; and again I ask, why are we programmed to? If you think humans need violence, pain and scarcity to appreciate peace, love, and comfort, why did God program them this way?
"I never said we should be puzzled by questions. I have taken several courses on the Old Testament in college and I have had a rather vigorous religious education through Church. I think that it is understandable. If we put ourselves in the shoes of the people of the time and keep in mind what they were going through and understood about their role in society and the world at large, we can understand. The mistake is when we take our modern view and look at a distant time and place and expect people to act and feel as we do now."
Again you didn't answer the question. "Why is there evil and suffering in the world?" "What physical evidence is there for a God?" "Do we really have free will?" All of these questions are widely asked in our time, and whatever you might think, there is no broadly accepted answer for any of them. It is extraordinarily clear that the existence of so many serious questions about the way God works is indicative of the fact that God is not working in a way we, modern man, can understand, today. "God works in mysterious ways" isn't some cheap throwaway line, it's often a serious answer to these questions. Why, if God resorted to genocide in the Old Testament because "that's the only way Old Testament peoples could understand him," has he decided not to act in ways we understand now?