To reinforce a sense of achievement ingame, our cars could use killmarks on their hulls to display proudly their MP kills for all to see .
I'm taking the example of the excellent EVE online:
Their system is really good:
- change the markings based on the manufacturer
- combine different shapes to showcase a maximum of kills in as very few symbols as possible
You know what, let's just copy this below shamelessly:
CE DO THIS PLZ!!