Slowking part of the problem with doing YI1 to get the goal sphere is that when you complete the level the game forces you to walk up the mountain to the yellow switch palace, and you have to walk back. This would imply two map transitions, and it's quite the trek up that hill. Many frames which eat up the time it seems you should save by skipping the cutscene. I think there may be a solution, though. If you cornerclip the pipe so you get crushed and die. This keeps you from doing the crazy trek up the mountain, with the tradeoff that you can't do the yoshi wings trick in yi3. I don't know how much time the wings trick saves, or how much time the goal sphere route was behind, so this may or may not actually be a solution
Where the fireball is I think is a potential death spot.
Eye of the Beholder:
Getting a goal sphere requires clapping chuck. YI2 only has two chargin chucks, which grant a naked koopa in the reserve box. Here is clapping chuck, he grants a goal sphere:
Here is chargin chuck, he grants a naked koopa: