Another idea is better disasters such as, if your close to a large body of water or on the sea shore, an earthquake would then trigger a tsunami. Or maybe even a hurricane that could destroy a large area, instead of those tiny tornadoes. Sandstorms also exist, and so do wars....Imagine if your world idea gets used, you could chose three...two...or even more countries to go to war! Quite fun i'd say.
And as for the volcanoes in sim city 4, they become extinct after one use. I would think that you should have a choice for an extinct, dormant (erupts unexpectedly) or active volcano.