In order to add more fun and more realism to the game, I suggest we add natural disasters to the game.
- Earthquakes: basically messes with the inside of your fortress. Dwarves are awoken and may sustain minor injuries as they are immobilized on the floor. Buildings such as workshops are destroyed, items are thrown randomly. Areas too large may cave in (which may solve partially the problem of one pillar holding the entire earth crust). But earthquakes can have benefits, such as opening ways to ore veins and caverns - but earthquakes may not occur in the magma sea (so no unfortunate opening to the circus) because of geological reasons.
- Hurricanes: not much to say. Just like a snow storm, but it's very violent and creatures may be thrown away and possibly killed. It also gives a new meaning for the weight of an item.
- Floods: a never ending rain that makes the water level in a river rise, until it reaches the entrance of the fortress and floods everything. The fun part is that a flood should behave just like a normal rainfall (and have the same announcement message), so you never know whether a rainfall is a flooding one, and when you find out it's too late.
- Meteor storms: okay, this one isn't quite realistic, but adds even more fun. A very huge and very hot rock falls in your fortress area, killing everything under it and digging down several z-levels. The result is a valuable ore vein, magnetite or even raw adamantine (the core of your meteorite) surrounded by melted rock, i.e. MAGMA. This partially solves the problem of magma being accessible only at absurdly low z-levels and also the new scarcity of metals.