Catch rule: where to draw the line

I'm going to create a hypothetical situation. If the NFL can create a catch rule which would make it consistent what the call should be (in all 3 cases below), and the reasons why, then I think they'd have a rule worth keeping...

Suppose a player has their arm as high as they can, and happen to stop the pass at that point. Their hand (or both hands) are on top of the ball. The ball starts falling, at close to the speed of gravity, but the player's hand(s) go with it. (There is no movement of the ball relative to the hands.) This happens until the ball is below the waist, so that is about half a second, an eternity in football terms.

Case 1: The ball continues falling. The player was pushing down slightly on the ball with their hands, but they never "grabbed" it. This should be an incomplete.

Case 2: The ball stops falling. The player has "palmed" the ball. Pretty obvious that is a catch.

Case 3: A defender has run up, and has swiped the ball out of the receiver's hands around the waist.
Is that a fumble or an incomplete catch?
There is no way to tell, at this moment, if this would have been Case 1 or Case 2 if the defender didn't swat the ball.

If you say incomplete, the defense complains that the (Case 2) receiver had possession for a full half second.
If you say fumble, the offense complains that the (Case 1) receiver never had possession.

What say you all?
(I'm guessing a hypothetical like this was part of the motivation for "going to the ground", but the existing rules are not clear in the wording.)

 

In the case of the Steelers it's a catch and a TD. In the case of NE it's not a catch. There, fixed that rule and it's cut and dry.

 

They ain't done Jackie Poo Poo with this rule. That ability to make a football move means it is still up to the ref

 

I think the only real change is "surviving the ground" is gone and replaced with making a "football move" which ends the catch process sooner. The other rules remain the same from what I heard.