I’m not disagreeing with you, I’ simply asking:
When G_d said Let there be light!, what would that event look like? Would it appear as if a light-switch were turned on to expose things as they already were - or was it the beginning of something new?
In that the universe appears to be expanding, it seems logical that matter has a point of origin - something “new”.
The conclusion I come to is that the creation stories you read in ancient literature refer to the creation of our own living world and local environment, and not to the creation of the entire universe. Our planet was originally a very dark sort of place, whence the huge eyes of the older creatures, particularly dinosaurs and hominids.
Other than that, the question you're asking does have an answer, but it's a longish story. Primitive people seeking to devise an astral religion from scratch today would invariably end up worshiping the sun and moon; nonetheless the two chieftain gods of all ancient religions were the two dwarf stars, Jupiter and Saturn, and Saturn in particular. The main religious festival in Rome was called Saturnalia and our sabbath is still called 'Saturn's Day' for some reason.
One version of this story starts here:
http://saturndeathcult.com/the-sturn-death-cult-part-1/a-timeless-age-in-a-purple-haze/
http://saturndeathcult.com/the-sturn-death-cult-part-1/from-purple-haze-to-golden-days/
http://saturndeathcult.com/the-sturn-death-cult-part-1/the-golden-age/
A more complete version which deals with human origins is here.
“or was it the beginning of something new?”
This one for the win!