People should use the freebie units more often, too. The shotgunner owns everyone at close range, and the minigunner is incredibly accurate even at a distance which makes it easy to get headshots with.

Also, what I always be sure to do is to throw my C4 before I die. You'd be surprised how often you get magical kills from your C4 lying on the ground somewhere, or how many points you get by taking a fat chunk out of that Mammoth that ran you over. Especially with the free units, don't be afraid to throw yourself at a vehicle, C4 in hand. If you die, it's not like you lose any money or points, and you can stand to gain a lot when you have no regard for your own health most of the time.