Is it just me or does slaanesh not fit with the traditional chaos warrior/raiders? Like khorne fits super well with the established chaos designs(pic related) and being a god of fighting and bloodshed is also fitting for what's basically vikings/conan barbarians.
Nurgle also looks good and the harsh conditions most chaos tribes live in also makes it believable that a tribe falls because of a pandemic etc.
Tzeentch is obviously the shamans/magic users/oracles of the tribes and mutants.
Slaanesh just doesn't make sense to me outside of rich merchants and nobles, they much better fit with elves and their entire perfectionist/stronger feelings aspect.
Hell even chaos ogres would fit more with their gluttony.