I don't think Call of Duty has that central figure they need to be the face of the franchise. Sure they have characters like Price, Woods, and Mason, but they only appear in a handful of games, and it's generally not the character you play as. Furthermore, the box art is always a miscellaneous soldier, it's more of a symbol than an actual character. Sure you can argue the Chief is miscellaneous because he wears armor and hides his face, but he's not Random Soldier 125. I'd argue the helmet actually makes him more recognizable and iconic, somewhat like a stormtrooper in Star Wars. I think out of the companies making Call of Duty, Treyarch is by far setting the standard of having a character you can identify for the most part. That being said, I don't think they're quite there yet, and they may never be. They're making their characters more unique, but by not adding them to the box art or showing more third person cut scenes they're hurting their ability to make an identifiable character.