If I were an Atheist

[Mister Agenda]

Now suppose we observe a universe that has discernible laws of physics that appear to govern how matter interacts and as a result the matter in the universe coalesces into stars that form into galaxies, that form into solar systems that cause planets to exist...

Earlier on the thread I've identified atheism, when it is understood as philosophy of life attractive to many people today, as the functional equivalent of a religion. I still think so (even though they don't); however that concerns only atheism's current social function, not the merits of its claims.

If we do observe an apparently lawful universe, then science looks for the laws. Science hasn't found a creator, nor looked for one either, mainly because determining what the laws are is easier. These laws are then whatever they turn out to be regardless of whether a creator is involved or not. There's so much myth and speculation surrounding the creator that this topic isn't really a fruitful arena for science. There's nothing physically measurable to date which could tell us anything about such a creator.

Claim-wise, the atheists are on reasonable ground while religions have overinflated their cushions on this creator business.

You seem to be a reasonable person, but atheism is not a philosophy (nor is it the sort of noun that ought to be capitalized, but I reckon that's your business), it's a position on one topic. It is not and can not be the functional equivalent of a religion for the same reason theism is not and can not be so. Or that the opinion that ice cream is better than bacon could be so. Atheism could be a feature of a religion, just as theism is a feature of so many (but not all) religions. But one opinion on one topic can't be a philosophy or a religion because it's so narrow. Whatever you're thinking of, it's probably not properly called atheism, unless confusion is what you're aiming for.

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If I were an atheist, I wouldn't care what the average theist does or really think too much about them. 

It's clearly not true that if you were a theist, you wouldn't care what the average atheist does or really think too much about them.