SHawk mentioned the other night that squad-specific skins might be an interesting identifier. I kinda like that idea, as squad art isn't really a practical identifier for me (stupid old monitor), but with the skins you could in theory get a decent idea of what particular group you were up against, without spoiling all the fun.
I'm not exactly sure how easily (or not) that could be implemented, but I just tossed that as as food for thought.
I'm not a real big fan of the personal identifiers, as I rather enjoy the suspense. Interesting ideas though.
Cheers,
hub