My issue is the only thing you can make visible on a transform node is "Position" which applies the animation curve to the transform directly as a paired unit. To create a vertical bouncing loop I would only need to adjust the "Y" position. I would much prefer to get the X and Y values displayed as separate inputs on the left side of the transform node. The implementation you've demonstrated is unintuitive.
I realize now that I could just animate the values directly on the transform node using keyframes, but the interpolation functions in the dope sheet don't actually seem to be working at the moment. I was hoping to make a smooth motion without manually keyframing an easing curve.
I really just wanna' slap those animation curve nodes on there and let them do the work without having to create a whole spiderweb.