The useless broken doll is empty, good to thrown to the abyss of the forgotten to be replaced, failing at it's own existence.
In canon, Murata is another vessel of the spirit of the Daikenja, and has all the experience and knowledge of his past lives, that's why I picture him as a haunted doll in my horror series. But Doll!Murata is a shell that was made to contain the curse of it's own existence, all of his past lives, all his experiences, all the knowledge, all the horror that the knowledge lead him, like all the past shells that was created before him. That's why in my first art, the broken part has eyes that look directly at whoever looks at them. But here, it's like a "What if" situation when the curse broke completly free, trying to find another shell to live within. Doll!Murata is a haunted doll that tries to live. To feel. To be...human again.