Help Needed for Chaos, Discord, and Destruction

For a little over a year now I've been working on "Zephyr", a conworld (constructed world) project that will hopefully serve as the backdrop to some short stories and role-plays when I get it to a finished state. (Some of my archived information is at CPWiki, but there's a heckuva lot more where it came from.) Normally, I would be content with keeping it to myself and just puttering along, but I've recently come up with a problem that may be fun to have some outside help with. Namely, Zephyr is too perfect.

Sure, Zephyr is more utopian and peaceful than Earth, and that's by design - but it's still too utopian. I've got a six thousand year history that has virtually nothing in the way of large-scale conflict or recurring social unrest. And that just won't do. So, if I could just get some people to suggest as many unpleasant things as you can think of to happen to my happy little island world, it would be very much appreciated ^_^ Feel free to look through what information I have, or hit me up for questions, since data on Zephyr is constantly evolving.

Here are some things I've thought of already, which may help spark some ideas:

* The Rhasiin: Great-grandson of the first man, Rhasis, was exiled from humanity in 72 CrE for committing the first sins of theft and murder (similar to Genesis' Cain) and became the patriarch of the Rhasiin, mountain-dwellers who remained in obscurity as the Aesiin, the sons of Aeus, continued to grow and prosper. When they return from their hiding hole, the reintroduction to the rest of the world probably won't be peaceful.
* The Fall of Man: Around 1322 CrE (rough estimate) mankind really began to shun the teachings passed down through tradition and started doing their own thing, so much that God came down and killed a third of the global population in a day-long earthquake called the Great Cataclysm in 2134 CrE, which is responsible for the number of islands on Zephyr. What kind of evil crap was humanity up to that warranted such a reaction?
* The Domination Wars: Following the Great Cataclysm, some of the survivors living on Jourth, House Deminare, decided it would be a good idea to conquer the huge island and make an empire. The Domination Wars lasted from 945 to 1075 CaE as different factions on Jourth sought to one-up each other in the grab for precious land. Fleshing out this period would be helpful.
* The Voltyin Landing: While not liable to spark a war (though you never know) the introduction of the alien Voltyini to Zephyr in 1272 AE caused quite a stir. Any cultural anthropologists want to help me map out their assimilation/resistance into human culture?

Feel free to ask any questions, too, since I need help with this overall concept and so far have been going it solo. Thanks in advance ^_^