As far as an argument that provides an alternative to creation from nothing, I think the idea of an all power creator would need to be an actual argument for it in the first place. It’s a philisophical notion and nothing more. There are a bunch of ideas out there as to how the universe formed that do not include any kind of god but of course they’re untested. Because something can’t be explained, the only thing that says is that we don’t know and that’s perfectly fine with me. The notion of a creator just fills in the gaps of our lack of knowledge even though there’s nothing beyond philosophy to back it up.
as we cant observe anything prior to a planck time, none of those scientific speculations are falsifiable. so a scientific sounding answer that is unfalsifiable is better than a philosophical answer that is unfalsifiable? obviously not. using “science of the gaps”, is no better than a “G-d of the gaps”. either way the answer is unfalsifiable, untestable.
we could at this point the simply say “i dont know” but that leaves you in the exact same position as any theist, in having “faith” that science can provide an answer even though it is unfalsifiable. this is an unaccpetable situation to a rational person.
so i will grant the idea of a perfectly scientifically explainable universe, infinitely cycling with no beginning or end using whatever theory you like, 'branes, strings, VP, etc.
now having this universe i can still ask, “why does the universe exist at all, where did this infinite chain of cause and effect come from?” in fact science demands the question according to its ultimate basis, the principle of sufficient reason (PSR).
so why does it?
did it bring itself into existence? obviously something that doesnt exist cant act to make itself exist, so we can rule that idea out.
that leaves only the idea that the universe doesnt need a cause. making it logically necessary. just as First Cause is to the theist. now we can rule out that idea because the universe might not have been, and therefore requires a cause to exist in any form because it is contingent. (it might not have been because there are an infinite number of possible universes.)
so where are we now? back to First Cause, a being necessitated by the existence of a contingent universe. so as you can see, even if you were right, you still wind up back at first cause, even with a beginningless universe. can you see how atheism is an idea that is dead on arrival now?