Allready adress itself into one thing yett everyone in these threads have posted different ideas that are off the topic from the OP. Yett i constantly have to link back to these threads for what i have said and or make them read previouse discussed ideas.
At the risk of sounding like i'm backseat moderating can I say that I don't mind lots of topics for maps really. Sometimes I think good ideas get lost in all the other comments, like your idea for a cave map got a bit less attention in the Volcanic map thread than it would have if it had its own thread.
Many of the current maps are quite wide, but the " ceiling" is always around the same level on each map.
There are big differences in heights, e.g. Fjords and Water Hazards have crazy high ceilings. If you wanted thunderstorms I would put them in Water Hazard, I think they would fit well on that map.
I do see the problem where people end up fighting mostly on a horizontal plane, you might need a map where you have to climb to the ceiling in the open, but once there you have a height advantage like the side of a mountain or a big open space with a tower in the middle with updrafts that would raise you to the ceiling quickly. You could also have a capture point map with point(s) in higher altitude locations (rather than sitting on the bottom of the map to cap) so you need to fight uphill or attack high and in the open to take points.