You're totally right movie-wise, but I'm one of those nerds who consume the extra materials and Hux stans build a lot of their mythos around his extended appearances. I don't think he ever had his own novel but he showed up in others, and in one of them, Phasma (two guesses who it's about), he is revealed to have poisoned his father with a beetle that Phasma supplied him with resulting in the aforementioned horrilarious death.