There isn't anything wrong with Hanoi if you stay the **** out of the middle building (I have a feeling Sofa King spends a lot of time killing people in that building with his Spas). I normally stick to the outside of the map and get some really good games.
I actually get my highest KD games on Jungle and Array but I can't ****ing stand how slow paced those maps play. On Array, I just flank the enemy team while they are camping behind the trucks all game.
On Jungle... I just camp the living shit out of the top of the hill until I get them spawning in the back behind the stone graveyard. Once they are spawning back there they are spawn trapped and there is nothing they can do about it, there is a nasty head glitch just outside of that spawn and you are nearly impossible to shoot once you are behind it.