If your changes fix breaking bugs in the game, go ahead and fix them. Try to avoid adding new features or altering the gameplay
Is it a problem if I made the game more polished?
It was unplayable and I modified the way the player interacts (it used to be automatic now you can use keys), added a tutorial so people could understand the game and changed some sprites to make signs understandable, other than making it more balanced and fair to play.