I started this idea in another thread.
What I gather many people don't like about random events is that they come out of nowhere for no particular reason. What I mean by this is, you are playing in this world about which you are acquiring a great deal of information as you go. Then suddenly, something materializes for which there is no precedent or traceable series of events inside this world you are spending all your time in.
I think that instead of some dice roll or game progression randomness trigger, there should be a system or systems in the game that fit inside the world/mythos and are explainable and justifiable. This will improve both immersion and replayability.
Here are my suggestions for event systems:
1. Astrology
Introduce an actual timeline for planetary movement such that you can map events to certain alignments. These events should be assigned from the pool at the beginning of the game so that save/loading doesn't affect them. Some events will be a once-off effect (i.e. loss or gain of gold/mana/etc.), others will be a threat that needs to be handled (i.e. monster/famine/etc.), whilst others still will have a duration equal to the amount of game-time that the planets remain in that particular alignment (i.e. + or - magic potency/+ or - spell research time/etc.).
Lunar and solar eclipses should also occur, with some eclipses lasting longer than others for the purpose of eclipse events with a duration (i.e. lycanthropy/total darkness/etc.).
Now this might be a stretch, but there might be some method to predict these events or at least when they are going to happen. This could be accomplished through the use of a spell, runes, a device/artifact, or a seer/prophet/soothsayer/priest/cleric.
2. Cause and Effect
There should be events that trigger based on a certain series of player actions. For example, if a certain number of predefined grand destruction spells are cast within a set time period, some cataclysmic event may result such as a chunk of land crumbling and falling into the sea. Or if a great number of bloody battles have been fought over a particular tile-square or map section, the land might become desecrated, which could mean anything from poor production to increased potency of corpses reanimated. The possibilities here are virtually infinite. Once players start to learn what triggers what, these situations can be intentionally caused as part of a strategy.
3. Location
Master of Magic had an excellent surveyor tool that could be used to make informed decisions about where you are going to build your next settlement. I don't know if anything like this is going to be put into Elemental, but this idea is inspired by that tool.
There should be certain devices or artifacts left by the Immortals or those before them that are positioned in different areas of the map when the map is generated. Building a city on that area may have a negative or positive effect, depending on the purpose of the device. Even fighting a battle on that area might have an effect.
Even if there will be a surveyor tool in Elemental, it should not be able to detect the presence of ancient devices, otherwise it won't be the unexpected surprise.
There have been many great suggestions regarding the scope, scale, timing, balance and type of events that should occur. I just think they should be implemented in a more meaningful way.