I haven't read her in about fifteen years, but I was a huge fan then and suspect it holds up. Dogsbody is indeed singular; I always liked A Tale of Time City, which if nothing else has an incredibly detailed and intriguing time-travel premise which I'd love to see turned into an RPG or some other kind of shared universe. I think the Chrestomanci series is somewhat uneven, but was always my favorite (it says something that I managed to spell "Chrestomanci" right the first time, even after all these years). It might read better in chronological rather than series order.

How's Moving Castle, too, absolutely. I never read the sequels (my school library didn't have them...) but I read the book over and over.