An issue that's been brought up a lot in terms of first person shooters, especially ones that allow you to create your own avatar, is the option to choose to have your gun in your left hand during gameplay.
Seeing as Destiny is all about customization and personalization, and as a person who is left handed, I would really like to see the option to display my gun in my left hand, and also to have options available to shoot by pulling the left trigger without having to go southpaw (I learned how to play regular, so switching sticks is not gonna fly).
I know a lot of left handed gamers would really appreciate this relatively small feature and I think that it would add, for me at least, another level of immersion.