The original creators were not Gods. They are fallable and their resources were not limitless. Might you make it worse? Sure. Anything is possible.
I think you should do what makes you happy. Isn't that why we own and play pinball machines? For happiness? If you can increase your own enjoyment by modifying something that is your own personal property, and it doesn't hurt someone else, then go for it.
Then again, this isn't just a hypothetical for me