The only good thing that ever came out of Microsoft's Mech Assault was a multi-player mode that would go like this:
At the start, one mech is the target, kill it.
Whoever kills that mech is the new target, kill it.
Of course, the terminated mech would respawn, and the round would go for the timer. I really resist the idea of respawning in this kind of game, unless it "really" makes sense for the match type.
What happens to me if I kill that Mech? Do I get a bonus?
What if I kill a mech that's not "it"?
What if the Mech who's "it" just leans back and lets the enemy rush towards him, so his team-mates can pick them apart?
How about this:
"First Kill" by Mech A. He gets a bonus on any successive kills.