I enjoy that Pratchett's protagonists have real-people problems, not fantasy-hero Chosen One problems, and that his novels concern the day-to-day workings of a magical kingdom instead of Great Quests (Maskerade is about the theater; Going Postal is, naturally, about the postal service). He's in the Douglas Adams leagues when it comes to true-to-life one-liners ("There seemed to be so much to do that she couldn't bring herself to do any of it"), and his dry, gentle wit of his Death is always a treat.
The particular story here, though, was muddled and rather depressing. The main thread of the novel seems to concern Agnes finding her own voice & sense of self-worth, to stop others from taking advantage of her, yet it's at odds with the Other Two Witches thread, which concerns Head Other Witch taking advantage of and manipulating others and trying to make Agnes give up her dream, which we're supposed to think is wise and charming. The treatment of poor Agnes, who isn't allowed much agency in the novel's climax, is more depressing than I think Pratchett realized, and the perpetually-downtrodden-outcast/bubblehe
Did like the Masque of the Red Death scene, though.