How cool would it bee for the mist to shift, as in not just expand to give more land for players but move as an organic conscious which can pull away or invade zones within the current player area.
In order to live within the mist or survive it when it drifts into a zone you would need a gas mask. At which you may given only limited time with your mask or protective gear to loot essentials or visit in or out.
This would cause players to move around and explore a bit more rather then just sit in their tribal area all day harvesting.
once again a suggestion but not high priority.