Which is it? Is gravity a force? Or some geometric curvature of space-time?

Gravity is a force borne from spacetime curvature.

GR is the theory of gravity as spacetime curvature.

As you are such a wiki fan - from Wiki

General relativity or the general theory of relativity is the geometric theory of gravitation published by Albert Einstein in 1916. It is the state-of-the art description of gravity in modern physics. It unifies special relativity and Newton's law of universal gravitation, and describes gravity as a property of the geometry of space and time, or spacetime

John writes

In order for this whole idea of space-time to make any logical sense there would have to be some evidence that this fabric actually exists. There is none. So why is it even taken seriously?

The whole GPS satellite system relies on the curvature of spacetime and the calculations that are derived from this view of spacetime as a curved "fabric".

There is no direct evidence in the existance of this space-time fabric.

As someone who is so fond of Wiki I would suggest that you look up General Realtivity and the verification of it in terms of the numerous observed effects of spacetime curvature. It has been repeatedly experimentally verified. From as far back as 1915 but most famously in 1919.

From Wiki

Similarly, a 1919 expedition led by Eddington confirmed general relativity's prediction for the deflection of starlight by the Sun,[7] making Einstein instantly famous.[8] Yet the theory entered the mainstream of theoretical physics and astrophysics only with the developments between approximately 1960 and 1975, now known as the Golden age of general relativity. Physicists began to understand the concept of a black hole, and to identify these objects' astrophysical manifestation as quasars.[9] Ever more precise solar system tests confirmed the theory's predictive power,[10] and relativistic cosmology, too, became amenable to direct observational tests.[11]

John says

If space is not a real physical thing where does that leave GR and SR? So there must be some direct evidence in the idea that space is a real physical thing.

Spacetime can hardly curve if it is not a physical thing now can it?

If space is not physical how can it curve?

If it does not curve how do you explain the extremely accurate and repeatable predictions of GR that are used by every sat nav system in the world?

Your alterantive theory will need to at least match the predictive power of GR.

Good luck.