Dunemeister, here is my initial response to your 6 points.
1) May I remind you of our disagreement. In post 16 laffy_taffy explained the difference between belief and non-belief and, given his lack of belief, asked why should he have to prove a things non-existence. Your reply was that it is the intellectually responsible thing to do. I pointed out the obvious absurdity in that remark. You then quoted philosophers who you claimed had attempted to do just that. They hadnt. And the arguments you describe simply point up the irrelevance of God, or gods.
2) Atheism is not a default position, and I assume no such thing. The mistake you are making is to think that anyone who is without belief in supernatural beings is obliged to make an argument against them. Nonsense! Atheism includes the most militant dogmatists, and it also includes millions of people who are simply without god beliefs. The difference is this: those who make assertions based on the question of supernatural beliefs, whether for or against, should expect to put up proper arguments, but it is pure unintelligent folly to ask those without god belief to justify that lack of belief; God isnt a truth, or something true of the world; nor is it a logical proposition, which, if denied, involves a contradiction.
3) God isnt a material fact, but a concept or, in the case of religion, a metaphysical system of belief. And nowhere have I asked you for proof; as a matter of fact I have said God cannot be proved a priori (nor a posteriori, for that matter).
4) It seems to me that if she has only shown that theism doesnt have very good arguments, then that is a perfectly reasonable justification for scepticism! And that is certainly true in the case of errant factual evidence, where the object is not to be found in possible experience, or where logical contradictions are evident. Under those terms the sceptic has every reason to remain sceptical. Someone who makes assertions for alien life forms, for example, is expected to provide clear evidence and articulate proper arguments to that end. So while it is the sceptics position to evaluate the claims for aliens, the onus isnt on the sceptic to find some reason for their non-being. Religious beliefs are not truths, not even in the inductive sense, and we do not have to consider them as such: for the concept of God is no different in any respect from all other metaphysical hypotheses. And to ask what arguments can be offered in favour of atheism necessarily presumes a belief that theism is false. It does not. As Ive already explained, it doesnt follow from having no belief that others beliefs are false or mistaken. But if you are asking for an intellectual examination of the arguments, then I for one have plenty to say on the matter. For example, a supernatural being sent his only son to earth to die for our sins, and then after three days the Son of God was resurrected and joined his father in heaven. Considered as an argument, what are we to make of that dogs breakfast? Nothing was achieved since evil (sinning) continues, notwithstanding this futile act. And we see straight off that there was no ultimate sacrifice, since God resurrected his human son (with no corruption of the flesh) after just three days, and we also see that a God of love wasnt above allowing pain and suffering to make a point.
5) In forum discussions I dont read links, but expect my adversary to make the argument. However, I am familiar with Plantingas argument, and youre right to say it is not without its problems. In one respect it is no different from all other arguments from free will, in that it instantiates and incorporates evil in order to justify it. Nowhere, nowhere in his argument is he able to assail the contradiction, except by allowing for a God who is not omnipotent and not the ens realissimum (evil, he says, exists in all possible worlds). This proposition is specious, at best, and also involves a further contradiction by weakening the Supreme Being. And Plantinga is stumped when it comes to the so-called natural evil. This is what he has to say: Natural evil is due to the free actions of nonhuman persons; there is a balance of good over evil with respect to the actions of these nonhuman persons; and it is not within the power of God to create a world that contains a more favourable balance of good over evil with respect to the actions of the nonhuman persons it contains. The Nature of Necessity (Oxford Press, 1974). The implication is there are for all to see!
Also, I dont remember saying that it isnt an important or interesting result! Actually it is, but the contradiction remains intact.
6) Theists, for reasons of their own, presume to pigeon-hole unbelievers. Theism and agnosticism are propositional, which in both cases describe beliefs. A-theism essentially requires no beliefs, despite the many highly vocal militant campaigners and anti-theists who are found under that banner. To have no belief in supernatural beings cannot somehow be turned into a claim about the world. And even the most vociferous atheist isnt obliged to come up with a competing metaphysical explanation or a further speculative hypothesis in order to provide an alternative to the one offered by the theist, since the very argument is one that questions the missing indubitability in such tenuous propositions. See my post, 118, 'It all come down to faith.'