Nothing new here...
Several of your arguments are flawed, as I will point out below.
Any “Crime Scene Investigator” (CSI) can bear witness to the fact that an absence of evidence is not evidence of absence! For instance, an absence of finger prints on the murder weapon is not itself evidence that there is no such murderer!
True that... But then you'd need to have further evidence to score a conviction, evidence which, in the case of any deity, is lacking. If this line of reason were to be followed, any old person who could not account for their movements at the T.O.D could be held suspect of the crime. I think I'm reading a little too much into your analogy, but fact is, multiple lines of evidence are needed to pin a suspect to a crime scene. In the case of deities and supernatural phenomena, that evidence is woefully inadequate if not nonexistent.
Let us suppose now we were to change locations, standing at the edge of the grand canyon with the same question before us and I ask you “Is there a bird flying around down there?” You could peer down into the canyon and find no birds within eye-shot but, this would not be definitive proof that there are no birds in the canyon!
Once again, true, but the only reasons not seeing a bird in the Grand Canyon would be inconclusive evidnce of the absence of birds would be:1-It is already known that birds exist from having seen them elsewhere, their nests, their droppings, shed feathers, video evidence and numerous incontrovertible lines of evidence and 2-It is already known that birds exist in the Grand Canyon...perhaps studies of their population densities have even been done making it almost a sure thing that birds do exist in the vista being surveyed. The same cannot be said of gods - what "evidence" we have of their existence is in the form of ancient, unreliable texts written by people with no understanding of natural phenomena, hence a need to explain that which they do not understand with all sorts of supernatural malarkey.
And that's just where the god hypothesis fails: it does not predict anything! Anything and everything is allowed, even if when viewed objectively it would ostensibly disprove it. The hallmark of any good scientific theory is that it makes predictions – testable predictions – that have the potential to be falsified under empirical scrutiny. “But God doesn’t conform to your high and mighty science!” I hear you say (basically the gist of your above statement). But if we can’t use science to test this claim, what are we to use? Are we supposed to uncritically accept the writings of ancient nomadic tribes who did not fully understand the way nature works? Religious writings are full of all sorts of far-fetched stuff, like conjuring tricks, talking animals, virgin births and the like (which, by the way are not unique to Judaism and Christianity alone – many are demonstrably copied from other ancient legends) which have been proven wrong by discoveries and advances in science. So if we were to use religious texts’ content as a scientific test, they fail quite dismally. And since it is claimed that they were written by an all-knowing “god”, we must come to the conclusion that there is something seriously wrong with this god concept. This is simply one of many proofs we can use that the concept of gods (and, by extension, the Christian God), at least as given by the religious texts we have, is simply incorrect. As an aside, this “God ain’t constrained by your laws” excuse is so often the rug under which evidence of bad design in nature, the apparent age of the Earth and other topics relating to origins are swept by creationism.
...a wild-eyed detractor...
Detractor: “Absence of evidence is evidence of absence!”
Christian: “Sir do I have a five dollar bill in my wallet right now?”
Detractor: “I don’t know.”
Christian: “Well, why don’t you stay consistent and say no! After all, isn’t ‘absence of evidence, evidence of absence?’”
That retort would be a false analogy. It would really be more like "Believe I have a five dollar bill or I shall smite thee!" And to top it off, we know that five dollar bills exist. A more accurate analogy would be our Christian buddy claiming to have a $3.27 bill, attendant with the previous death threat! The fairness of such a proposition is, to say the least, debatable.