So I'm the kind of person who never care about armor look customization, especially if I have to pay for them. But wouldn't it be awesome if there was a customization option which would display you're kill since the last time you died on you're character/vehicule. Kinda like this:
http://www.guzer.com/pictures/car_hit_count.php
(if it doesn't work for some reason just google car hit tracker, should be pretty clear what I mean)
You could have different option, like for vehicule/aircraft/infantry kill count, or faction kill count stuff like that