Khaleans are a very romantic culture, which translates to “good” in our fantasy literature sensibilities. Go along with that, it’s probably more worthwhile at first than undermining it: for instance, destroying or corrupting the poor, noble savages is going to be very, very tragic, regardless of which side player characters happen to be on.
Alternatively, consider my Ammeni Wars campaign, in which the Worst War becomes regional as a hero band travels to Orania and wins the Senate of Kalderon to their side; even if victorious, the epic heroes are going to have a bitch of a time with the Ammeni reconstruction: what do you do with a nation like that?
I have the impression that the Khalean capability for time travel has largely been neglected in practical play, possibly because it takes a campaign to such radical directions. Still, one day I’m going to play an assassin from the future, his only hope to kill the man who would sell his people to eternal slavery. Other basic directions to go here are the Celtic olden goldies, like shamed heroes cast out of their tribe, bards seeking their art in the oddest places, romantic troubles caused by the moietic taboos and so on.