Welcome to the board. You presented a great deal of information in a very impressive but complex presentation. Perhaps a bit too complex for the known simple mathematical methods of the Ancient Egyptians. Please don't misunderstand their simple methods could produce relatively complex results. Given in the Rhind Mathematical Papyrus Ahmes states: “Correct method of reckoning, for grasping the meaning of things and knowing everything that is, obscurities and all secrets.”
A good book I use as a reference is ARCHITECTURE AND MATHEMATICS IN ANCIENT EGYPT by Corinna Rossi, Where in the first sentence of the first paragraph on page 87 states:
"As I have shown in Part I, concepts like л or Φ did not belong to ancient Egyptians mathematics and therefore could not be used by the ancient Egyptian architects. Their presence in the plans is mainly due to our modern interpretation of geometrical figures that compose the plan on paper."
In the second paragraph he states:
"At any rate, the total lack of evidence has never prevented people from suggesting more or less complicated theories."
I like and recommend Rossi's ARCHITECTURE AND MATHEMATICS IN ANCIENT EGYPT since it seems to be free of many assumptions regarding Ancient Egyptians methods vs the assumptions attributed to them in many other published works.
I am curious as to see how pi, radians, angles and meters actually relate to the unit fractions, seked and cubits of the Ancient Egyptians? Now unfortunately there is no proof the Ancient Egyptians were even cognizant of pi. Evidence dies demonstrate they worked in unit fractions, seked and cubits in their own binary addition system of multiplication and division (by inverse multiplication) by the process known as the Eye of Horus based on the powers of two: (1/2, 1/4, 1/8, 1/16, 1/32, 1/64) equaling 63/64.
I will mention there are always those unspoken and unanswered questions present in the plethora of claims attributed to the Ancient Egyptians: How did they know this? By what means were they able to accumulate information attributed to them in these claims? And last but not least correlation does not imply causation or confirmation.
I can agree with some of what you say. Regarding some of the sources and complexities you attribute to the design of G1, I am very skeptical without further supporting evidence relating to Ancient Egyptian methods.
Also let me mention, just for the record, your interpretation of cubit length and purpose do not coincide with the original Royal Egyptian Cubit length determined by Petrie in section 141 of The Pyramids and Temples of Gizeh, W.M. Flinders Petrie, 1883: “The values of the cubit and digit, found in use in the cases mentioned in this chapter, agree remarkably closely with what has been already worked out. For the cubit I had deduced (Inductive Metrology, p.50) from a quantity' of material, good, bad, and indifferent, 20.64 ± .02 as the best result that I could get; about a dozen of the actual cubit rods that are known yield 20.65 ± .01; and now from the earliest monuments we find that the cubit first used is 20.62, and the mean value from the seven buildings named is 20.63 ± .02. Here, then, by the earliest monument that is known to give the cubit, by the mean of the cubits in seven early monuments, by the mean of 28 examples of various dates and qualities, and by the mean of a dozen cubit rods, the result is always within 1/50 inch of 20.63. On the whole we may take 20.62 ± .01 as the original value, and reckon that it slightly increased on an average by repeated copyings in course of time.”
Based on all available evidence, I am unable to find a reason to disagree with Petrie's assessment.