In the city:
Get a sniper in the corridors and press F3 (move out). Take the 3 corridor spawns first, then get the spawn under the 2 ligned up against each other. What remains is the N and the carbon freezing chamber. Move to the top right corridor or wehevrer they are heading and clash, use rockets or assault.
You can snipe, but early in the game its better to get spawns first. Afterwards you can snipe in the corridors. For the spawn under the corridors (South) you'll need to get a few first though; you also wont make the jump if you just jump down (jump to side of the wall, and heal if you're pilot)
In the air map:
Use the vehicles of course, get AA first and then enemy aircraft. Get spawning vehicles and those runnign to them, you may have to help getting the middle spawn fist on the ground and afterwards fly around it, just so you wont bleed.
-"The glass is neither half-full nor half-empty: it's twice as big as it needs to be."