This is a pretty good catch, I must say. Although I don't necessarily agree that the main character is your ghost. It makes the guardians feel insignificant to some degree. With that being said, I do believe we are meant to feel insignificant. Not because of ghost but simply because we literally just "woke up". The tag line for the game is "Become Legend", we are not legends yet and won't be for a long time therefore we are merely body guards at the moment. As the story continues, some of us will begin to step into the light and become Legendary. Think of Master Chief, he is a legend in the the halo series. When we first step into his shoes, he is already known. He's already the Master Chief. we are not there yet and it will take time to get there, but when it arrives, the Darkness will be shivering in their panties.