Just a little point... if the Earth had diameter of 12,7 millions of meters, (without furthermore considering that being the Earth a flat disc it should have a double diameter, thus making unrealistic the circumnavigation times in the two emispheres, southern and northern) assuming that the sun, that it is supposet to be 93 millions miles (148mld meters) far away, hits with his warm rays the Earth's surface, all the surface as one would be contemporaneously illuminated and, according your model, there would be no season and no day-night alternation, as the sun is too far from the Earth to product a localized illumination effect, just try with your desktop light.