Why would you expect gravity to be constant across the planet if it is an oblate spheroid with non-uniform density and varying composition instead of a homogeneous sphere?

Congratulations, you just disproved the modern science text books....

I said the above because i expected you to know the current model of earth, and know how mass, in the shape of a sphere would display gravity. (basically, the anomalies are cancelled out by the size of the planet. Uniformity is assumed because the planet doesn't have a huge wobble, which it would if one side was heavier than the other. The mathematics works out such that all the mass is considered to be at the center point of the earth)

Furthermore, the gravity is not just a little bit off from being uniform, it is WAY off.
So much so, that there is a scientist who believes that there are micro-blackholes inside the earths crust.

I doubt you have seen any disproofs of flat-earth.
You have probably seen videos which just discard their claims.
But, here is the root problem:

• You can see things over the edge of the horizon.

The US published charts on how far away you could see a light house.
A guy worked out from their height and position, that this was beyond the edge of the horizon.
So, you have to see through the water to see them at that distance.

To drive this point even further, you can see these light houses from even FURTHER on still, clear nights. (so it isn't even a question of it being beyond the horizon)

And now, people are taking infrared photographs of cities WAY over the horizon.

Of course, this could be because light travels along the surface of the earth. (not in a straight line)