But you would still need Assist kills. Without them KSing would be a problem, especially in a team game where more than one person is shooting at the same enemy.
I like assist, but it's not required imho. Whoever does the final shot gets the kill, but it's all about the objective. Like I said: I couldn't care less that they killsteal me when I'm defending the HE charge.
Getting killstealed in a game like COD is way "worse" because it reduces your score and KDR, while these two factors are not important in Brink to be good.