Thanks for the in-depth input :)
As for the controls, I wanted the vacuum to be "free floating" so the player could vary the amount of suction based on distance. This should work better once I improve the physics. The reason that the ball likes to "bounce" out of the goal is because the goal is a "slope", and the slopes physics aren't quite good enough to handle it. I have plans to add a "targeted" mode to the vacuum, where you lock onto the nearest object (there will be other moveable objects for puzzle aspects later on) at an adjustable depth (third mouse wheel) for easier moving.