Great idea, but the switch cool down is a great idea and needed.
Also, the level with no platforms and inverted gravity is not intuitive- some visual indicator of when you are switching gravity fields is necessary.
The platform level also needs some visual indicators of waypoints for the platforms and some land markers so the player knows they are moving (if all are moving the same direction at the same rate, looks like you are standing still)
Finally, the last level has some bug working to do. Sometimes the platforms fell at different speeds. Also, I would switch when near the close wall, but my guy would sometimes switch to the middle of the other side instead. It certainly is a tough level!
Cool game, keep up the good work!