While I know the game has little options for the creation of the face for your character, there's been a bunch of features missing that most other MMO games have had for years now.
What I'm talking about is the ability to change your character's hair, hair color, and so on. Bungie could easily do something about this; a small kiosk or vendor for changing your looks would suffice. Some of us are DEFINITELY regretting our Guardian's looks, and others like me simply want a little touch up without having to create an entirely new character just to fix one little thing. Plus, this could open up the avenue for more customization options. Bungie could make more hairstyles, more faces, more warpaint, and this opens up the avenue for possibly community created content as well! They could even do it for Silver (100-200 a piece).
Alongside this, for those that are happy about the appearance of their character, how about the option to have our helmets off? If literally every other Guardian/Warlord/Iron Lord NPC can do it, so should we (and if you're a Hunter: Hood off or on as well).
While I understand this is a VERY small part of the game, it doesn't have to be. For me, simply seeing my character's face in the Tower and in the Character screen isn't really enough. I'm proud of my character so I want to be able to show it.
This would be an amazing addition to the game IMO.