I must admit the game started to feel a little silly when the bouncing ball appeared. I liked the freedom of movement though and continued to enjoy the game. I also hadn't played your previous games so I didn't know the "history" of the ball.
I kinda rushed towards ringing all the bells, and explored only like 50% of the world. I thought I would continue playing the rest of the game after I finished the main story, but the ending was a big "Fuck You!" from you.
Where it gets really frustrating, is when there are so many rooms with too many traps and puzzles. It becomes less about exploration and more about trying to figure how you wanted an area to be solved. Moments where the player has to guess the mind of the developer make a game annoying.