Going north means you will be on a large open stretch. There are a few good footholds that, if you can secure, will help you in your advance. Some of these would be the North Hill Ruins (the ruins by the elm tree) and the square delapitated building to the north of the elm tree. A rush is the most effective tactic. Taking the North Defence Hill ruins will be a challenge. An alternative north route to take is to go north, then swing east through the north hill ruins and down to the destroyed building. Also if you go north, you can go prone behind the burned out car at North Extraction Point. This is an excellent spot to fire or snipe N. Defense Hill.
Going South gives you the advantage of elevation and cover, however south is hard to attack because of the urban setting. Snipers can be hidden in any of the buildings in the valley. A south assault can be more direct, but must be done slowly to be completed successfully.
A central assault is a more dynamic situation. Often you will be pinned down behind a square white building in the central valley if you try to go directly central. While in the central valley, you can swing left and go north up the hill to Town Hall. From here, you can take out opposition that might hinder your advance. Also, running from the hill to the blue building provides cover from the "Exploit" building.
ADD: Rushing north is a good tactic if you have a M-16, a sniper, and a SAW. The sniper watches for any heads that pop up on northern ruins hill from the ledge opposite from the extraction. The SAW goes prone on the ground under the ledge and covers the M-16 as he 1)rushes to the 2-windowed block thing far down on the left and 2)frags northern hill from the side. SAW follows up directly after.
The best place to cover the Southern passes is to enter the building with the two windows and crouch. If you stay stationary in the crouched position, especially on the right side, your head is almost invisible to their rushers. Scan the hills and the South pass and take out any assaulters, and watch out for a flank later in the round.
The next best place is the balcony to the left. Not as much cover as the first position, but definitely worth sending an extra man.
Covering the North you have many options, but all get you picked off rather quickly. There are the walls/destroyed buildings to provide cover. Keep an eye on the hills, the Town Hall, and the destroyed building.
ADD: A useful North tactic is to rush up the northern valley into the North Hill Ruins (by the elm tree). From here, you can go further north to the square broken building, and you can cover town hall, as well as guard against attackers rushing to North Defence hill. Beware of flash and frag grenades, keep on the move to avoid being taken out by a grenade.
ADD: Rushing Town Hall is a good tactic that the assault usually doesn't expect. As soon as you spawn, run across the road and up the hill leading to Town Hall. Once you get to the barrier separating you from the Town Hall, go prone and slowly crawl across the open strech of grass. Once you are close to the actual building, go LEFT instead of RIGHT. You can now open fire on attackers attempting to go through central hill, and also any prone snipers on either the hill close to the extraction or the open building roof in the village. If you spot enemies on south hill, you can rush them from the rear at this point.