Complex sentence: Along the way, John has compulsively amassed a vast collection of art and pop ephemera, in doing so he decided to slow down his label work and focus on manufacturing a new line of toys and publishing art-related books.
Split into simpler sentences: Along the way, John has compulsively amassed a vast collection of art and pop ephemera. It allowed John to finally slow down his label in order to work and focus on manufacturing a new line of toys and publishing art-related books.