This mission is not bad as long as you stay back and snipe. Getting too close on Veteran is suicide and will only get you dead and frustrated. Be careful when the helicopter troops came down the hill. If you stay back and snipe from behind the cars and other cover, it should not be that difficult. Also be careful in the house with Nikolai. Use your night vision and shoot all the enemies before they can shoot back, especially if they are still behind cover. I find it helps at the end to throw a flash grenade into the last room, to make killing the flashlight guy easier.