Of course you can introduce this ominous celestial gravitation as something that just by definition acts in way that it fits to all observations. The question is only how far you can go with this attempt? If you read through the explanations of this celestial gravitation it seems to be a quite selective force. It always jumps in if with the denial of ordinary gravitation you approach some problem. On A it acts in that way, while on B it acts not or differently from A.

But that's not the way how the modern way of mechanical theory works. We do not have a law for the precision of the earth and another one for the precision of toy gyroscope kids are playing with. We only have one law for the spinning of mass. And these laws are universal also in a much broader sense. They are the same at any time, at any place and in any direction, and invariant upon scaling, you make no assumption about that during their derivation. I can only encourage everyone to read through a book on mechanical theory to see how to derive so very different things as the Kepler laws, the Euler equations or the equations that describe the motion of a pendulum in a very coherent way from the same starting point.

Compared to this all this flat earth stuff is a patchwork of ideas, sometime obviously even contradicting each other.