1. It isn't any more supposition that the physical constants have changed than it is that our sun is doing exactly the same thing here and now as they were doing there and then billions of light years ago that far away from us.
2. Logic doesn't analyse anything btw. For the purposes of scientific investigation, whatever you've been told about anything, God or otherwise, can be safely set to one side if it can't be verified with your own observations and experiments (fyi, reading what some unknown author wrote thousands of years ago is not an observation or experiment).
3..Well, as much as they don't say it, it might as well be proven fact. also, I agree with Astrophile here, and he explains this perfectly...
4. Newton's Theory of Gravity is another theory that wasn't entirely accurate. As Gould said, "Einstein's Theory of Gravity replaced Newton's in this century, but apples didn't suspend themselves in mid-air pending the outcome, and man descended from ape-like creatures whether we did so by Darwin's proposed mechanism, or some other way yet to be discovered." - Even if the current scientific views on the age of Earth, Universe, Atomic Theory, Germ Theory, Einstein's Theory of Relativity or the Theory of Evolution aren't entirely accurate, the corrections will be minor and the broad underlying principles they eschew wouldn't be fundamentally altered, let alone discarded for an entirely nonsensical view of a 6,000 to 10,000 year old earth and universe, with 'kinds' created in their original forms, etc.
4. Okay. A few things here, Much of the world's uranium reserves are in paleozoic unconformity type deposits, that is to say, in layers of earth between 2.6Gya and 0.5Gya. Most of these uranium deposits are further narrowed down to either 2.6Gya or between 1.6Gya and 1.2Gya timeframes. Prospecting for pretty much anything in the ground is now observant of a community database that records the layers of exposed rock, their age and where they are all over the world. Oil deposits in particular are dependent on buried biomass accumulation over millions of years, an accurate knowledge of the age and location of a prehistoric swampland, marshland or oceanic microbial flourish is a huge advantage in today's highly competitive oil and liquid petroleum industry. If you think mining and oil companies just wander out of their cities and just start looking around randomly, then you're about 150 years out of date. Through this science, these companies have been able to supply our civilizations ever insatiable thirst for fossil fuels and mineral resources with ever increasing efficiency in refining and accuracy in identifying the next crude oil or resource deposit.
5. A side note - it takes about 20 metric tonnes of plant matter to get a kilo of crude oil. (There's about 3.2kg in a gallon btw...) -this would be almost 2500 tonnes of plant life per barrel of crude oil. At the end of 2015, we were consuming around 97million barrels of crude a day. The amount of plant and animal matter required in a 6,000-10,000 year old earth to get just a year full of oil we use (that's just over 35 billion barrels) is absurdity of the highest order, that's not even considering the amount of time required to get these deposits...
6. So you're ignorant on the value of studying ice cores? Colour me surprised. The scientific community hasn't any requirement to "prove that the earth is old", so that nonsense can be set to one side. We can map out the climate from these ice cores for the last 680,000 years and we've found ice cores that go back to 1.5Mya. The most accurate and researched ice core is of course the Vostok ice cores, these date back to 150,000 years and have been dated using at least 5 independent methods, all correlating to the same result. From this, we've been able to map out, as you say, global climate over that time. If you dispute that these ice cores are accurate, I'd be interested to know why past the standard YEC's "Scientists might be wrong" dismissal.
7. According to Genesis 1:1, God's first act was to create the heaven and the earth, light came after that. Apart from that, everything else you've said here seems creative & ad-hoc. As I mentioned earlier, singularities would leave tell-tale signs - in the same way we know where black holes are even though we can't see them. A singularity that warps light & distance to the extent you are trying to suppose would be about as obvious as an intergalactic boot to the head.