IMO Kings fall is better because every player is critical to succeed and communication between the whole fireteam has openned up. The bosses are a huge improvement and not to mention the environment blows VOG away. The jump ships, bridge, giant pendulums, golgoroths cellar, Oryx arena. Even the rewards look a lot more interesting- the ghost shell, weapons, and armor skins. KF is pretty much an improvement on every aspect.