Fundamental Atheism and the Conflicting Ideas Problem.

...why do we have to start from the point that something exists without evidence, and then we have to disprove it? Isn't the idea of God the biggest strawman of all? Maybe I am being too simple here, but shouldn't we have evidence for something before we say it might even remotely exist? Shouldn't a rational idea be based on whether or not the idea is internally consistant and does not contradict itself? If a god did exist, then where is the evidence that makes more sense than the blind dance of matter and energy conforming to natural laws that not only explain but predict natural phenomena? What is the nature of any god, even a god that makes something and leaves it alone? Where would this god come from? What made this god? What makes this god what it is? How could a god be part of the universe that it created? Or, if a god is outside of the universe, then how could it have interacted with the matter and energy of which this universe is made? Not only is there no evidence for a god, rational thought points to no possibility of a god whatsoever. So, how could holding the position, "I know that no god exists!" be any different than, "I know that pink flying elephants did not build my house!"?
I fail to see how you could have a fundamentalist atheist. Fundamentalism deals with holding a belief no matter what the contradicting evidence says. But there is no rational contradicting evidence against atheism! The only possible contradicting evidence against atheism would deal with individual, subjective belief. Subjective beliefs do not necessarily have to rely on rational thought. So how could we compare the two? The weight of evidence relies on those making the claim, not the people who ignore the claim until reason and evidence warrant its investigation.