I think if it's point sized, you're allowed to imagine any shape of cat. :D

For a uniform gravity field it is essential that the cat is spherical.

It's also crucial that the point-sized spherical cat is not spinning, because that's a quick way to get a ring-shaped cat.

All black holes I've run into are cat-shaped, yet they have uniform gravity fields around them.

That's strong evidence that these are spherical cats. I take it that you are unaware that cats creating a non-uniform gravity field will deviate from their normal spherical state. For instance, cats on planet earth will have all kinds of non-spherical bits sticking out and this in turn gives rise to our distinct and non-uniform gravitational field.