Here's another "unpleasant" yet welcome event: All of a sudden a fullstack army of Goths invaded Carthage! And finally the Huns are a powerhouse. No Vandal invasion of Africa yet, though. Never seen it happened, not in a mod or vanilla.
The only thing I could wish for is for the Slavs to invade eastern Europe and try to settle in Thrace, Greece etc. Now they always ( more or less ) end up in Spain or France.