In class, we completed animation exercises to study timing. Animating a ball on a path teaches you how different surfaces affect speed. If I were to redo this exercise I make would add more frames to the peaks in the path because the ball will have a harder time travelling up than coming down. Smear frames would allow the ball to move faster as it travels down the curves and make the motion more dynamic.
Straight ahead animation is best for animating elemental effects such as fire or water because the movement is less predictable. It can also be great for exploring movement and warming up before starting another animated project.