Loving this!
And i totally agree on the asteroid / supervolcano (or just ANY volcano) suggestions.
Well, basically any random events that affect the terrain, DO WANT

Volvanoes (could maybe be tied to the krakatoa tile?) that spawn tundra 1 tiles around them, with a random chance for an additional tile (so it looks somewhat asymmetrical).
Why tundra? Because it looks kinda gray like fresh solidified lava, and has the same kinda properties (low food, desolate, but useful to farm on etc).
Asteroids that spawn 1 hill in the middle (as the "rebound" of the soil), with 1 tile flatlands, then 1 tile of hills around that. Or just use the barringer crater tile, looks so good so why not

It'd be cool if the asteroids could change the terrain though, maybe flood an area if it hits land, while the volcano event could create land when it happens in the ocean.
That way you'd have 2 events that kinda make up for eachother, one makes more water, one makes more land.
And another idea i just got, a sort of coral reef event, or algae blooming, idc what you call it LOL, that adds more shallow water to potentially create new 3 tile length shallow-water "bridges" between very nearby continents, for instance if a continent is 1-3 deep ocean tiles away, this would create shallow water between them, opening up new possibilities in the earlygame or lategame (ironclads).
edit: i must admit, the earthquake event is dumb.... i just started a new game and the second i had surrounded my capital with 3 farms, the earthquake triggered and all the work was for nothing.
I mean, i love random events, but when they are so severe that they cripple your entire empire, thats just pointless.
In regards to the above suggestions, i think earthquakes should be like the suggested asteroid / volcanoes, random low chance of happening at a random place in the world globally, NOT centered around one of your cities (earthquake magnets?).
The main issue is that having 6 improvements destroyed, even in the late game, is just not fun. Its so tedious to rebuild all those improvements, in pure gameplay boredom.
Even just repairing 6 improvements is tedious enough, imo such an earthquake should only affect 1 improvement, that way if you have bad luck it doesnt completely negate all the other good work you've done up til that point. (or cripple the AI due to a bad dice roll)
If anyone could tell me what to edit to remove the earthquake event, i'd be grateful
