I've always thought that adding some kind of other natural disaster could make the game more fun and challenging and in this case, it could be earthquakes. This is what I have in mind:
World generation
When generating the map, each tile has a threat level of experiencing earthquakes: low, moderate or severe. The storyteller and difficulty chosen at the start could also enhance this, with higher difficulties resulting in more frequent and damaging earthquakes, and lower difficulties resulting in fewer and lighter etc.
In-game effects
Research
Finally, one way to combat earthquakes would be to add a new research branch called "earthquake engineering". Researching this could result in earthquake-reinforced walls being unlocked, which are much stronger and more resistant etc. Of course for maps in low-risk zones, this would hardly be necessary.
Just some basic thoughts from me.
World generation
When generating the map, each tile has a threat level of experiencing earthquakes: low, moderate or severe. The storyteller and difficulty chosen at the start could also enhance this, with higher difficulties resulting in more frequent and damaging earthquakes, and lower difficulties resulting in fewer and lighter etc.
In-game effects
- Earthquake would be an event triggered in-game by the storyteller, with three different flavours - minor, major or devastating. They would first be marked by a shaking of the screen.
- In-game effects would be as one would normally expect. Gradual damage to walls and structures, with more powerful earthquakes completely destroying wall tiles. If enough are destroyed, this could trigger roof collapses, injuring colonists.
- Also, tall free-standing objects (like wind turbines etc) can be knocked over/destroyed which could also injure colonists who are nearby.
- I'd also suggest a temporary mood penalty to colonists (especially colonists with more cowardly traits), as earthquakes tend to (expectedly) frighten a lot of people.
Research
Finally, one way to combat earthquakes would be to add a new research branch called "earthquake engineering". Researching this could result in earthquake-reinforced walls being unlocked, which are much stronger and more resistant etc. Of course for maps in low-risk zones, this would hardly be necessary.
Just some basic thoughts from me.