lol well back to the earlier posts, at least in a canopy type map fog and mist would actually make sense in a jungle/old forest environment. the clouds in canyons are functional but they make you wonder why they are there
i would really like a map in a cave, not the normal kind of cave you think of because why would taking an airship in a series of small tunnels make any sense. im thinking of a cave with a large-ish oculus in the top that would facilitate dropping in supplies by airship. the obvious choice for this kind of thing would be a dormant volcano with a large empty magma chamber, or a very large water cave (think what gandalf fell into

). this could be some sort of old base set up by a forgotten military power or a settlement of a group trying to evade and hide, perhaps a factory of some kind using the geothermal energy of the area (if its a volcano that is). no matter the past reasons, it would be rich in technological ruins the current inhabitants of the world desperately need.
The ruins of the previous occupants would have to play a major role in shaping the "landscape" of the map. so it would have to be some rather massive infrastructure, but in a chamber that can hold airships easily, that should be no problem. The part where it gets interesting would be the fact that since these are technological ruins long without power, the only environmental light source would be that of the opening in the middle. The shadows would be the major player here as there would be no clouds unless the atmospheric conditions were absolutely perfect.