A sacrifice to be made

I hope to not offend too many people with the nature of this post. I've been thinking back on a lot of Christian apologists/theologians and their reasoning why Christianity makes sense.
In all reality, there does need to be some kind of explanation, because Christians have to answer to the question why we worship some guy who the Romans crucified two thousand years ago.
So the explanation usually goes that Jesus had to die in order to sanctify humanity once again. St Augustine said that humanity was stained with the sin of Adam, or original sin, and thus every one needed saving, no matter how good they are. This leads to the Christian emphasis on baptism and more especially the Catholic defense for infant baptism. Karl Barth re-emphasized Augustine's words and said that Christ was almost like a second Adam, but that His sacrifice by far overshadows Adam's sin. Athanasius said that Jesus had to die in order to reconcile us with God, and St Anselm said that a God-man needed to pay the price for our sins. Hans Urs von Balthasar said that Christ had to endure all things that humans endured in order to have lived a truly human life, including death.
All these men, I think, were right. It is true that humanity needs saving. However, I will respectuflly disagree with Barth and Augustine and state that there is a lot more than the fall of Adam that needs reconciling.
I think of where man is now, and where man has been before. We consider animals to be sinless, but this is because animals are innocent and stupid. We humans have gained great stores of knowledge, but what have we done with it? We possess the ability to destroy all life on the planet several times over. We have long histories of bloody wars, some lasting many, many years (the forty years' war and the hundred years' war, for example). We take away people's freedom and put them to work as slaves, or in internment camps, or traffick them, or put them to work in sweatshops. We take revenge for our perceived wrongs. We take more than we need, limiting how much others can have. We elevate ourselves above other people or debase ourselves below them. We steal, cheat, lie and take no heed for the damage we do.
And that's only what we do to each other. We also have many sins against nature. As the most intelligent of all species on the planet, we alone have the ability to help maintain the natural balance of the earth. But instead we build polluting factories. We kill off native species and introduce foreign ones. We spray pesticides and herbicides into fields, killing off naturally occuring life and poisoning the ground water. We deplete forests, ore reserves, oil fields. We drain wet lands to build mini malls. We clear out rain forests for cattle grazing. We take and take from the earth and never think to give back. Man is the only animal that can prevent ecological disaster, yet it seems that all we do right now is cause it.
So, while the weight of Adam's sin might be a heavy burden for Christ to bear, I think it is nothing compared to the many thousand times since then that we have damned ourselves as a species.
This, then, is why I am a Christian. I think with the damage we have done and the sins we have committed, it would take nothing short of a miracle, and no one else but God alone to pardon them all. If there's any hope for the human race, I think it came about two thousand years ago in the backwater regions of the Roman Empire.
And as a Christian, I think the command to help build the Kingdom is a very real command. And this command does not simply mean proselyting to the non-Christians, but living in a way that shows that we are willing to live without the sins that we have for so long embraced.