I have noticed that my players have been pretty quick to compartementalize chaos stuff into being of one of the four chaos gods based on soem pretty narrow definitions. Khorne is blood and violence, Nurgle is disease, Slaanesh is sex and Tzeentch is magic. I am planning to shake those preconceptions a bit, so I am trying to come up with other aspects of the gods powers that aren't quite as usual.
Nurgle: Famine and slavery.
Slaanesh: Food and arts.
Tzeentch: Political upheaval and breaking of taboos.
Khorne: Hunting and martial honour? Honestly, Khorne is the one I'm having the hardest time with.
Anyone else have some other concepts/aspects for the gods that are outside the usual cliches?