Stop? Somewhere around 1/3 of the diameter for a 45deg sloped pyramid, adding more layers would start projecting off the sides, offering no additional support for the new layer. Drawing a teardrop shape with a perfectly circular head and perfectly tangential tail with be the same as a cross section of this planet/pyramid
I don’t see why the base would have to be flat. It could have a spherical volume carved out the bottom to accommodate the goofy little planet below
You wouldn’t even notice seams. Line the width of human hair if you’re using similar to Egyptian pyramid blocks
What would you do as the side length of the base approaches the diameter of the Earth
Stop? Somewhere around 1/3 of the diameter for a 45deg sloped pyramid, adding more layers would start projecting off the sides, offering no additional support for the new layer. Drawing a teardrop shape with a perfectly circular head and perfectly tangential tail with be the same as a cross section of this planet/pyramid