A noun is the name of a person (Tom), place (Paris), animal (horse), tree (rubber), plant (chrysanthemums), thing (bottle), a quality (honesty), a group (crowd), etc.
A pronoun is not just a substitute for noun; it is much more. I, we, you, they, he, she, it are some basic pronouns while myself, ourselves, themselves, himself, herself and itself are a few others.
I wonder what the hell is the good of rearranging words after unnecessarily breaking them off! Do students really add to their language skills after all? I have no answer to these questions. Honestly, it is time educators sat around to discuss when they would like to stop this fruitless activity!