You have missed out. He's my favourite author ever, I think. Tbh, Colour of Magic was horribly boring, my favourites were Unseen Academicals, Making Money, Going Postal, the Monstrous Regiment, the Hogfather and Carpe Jugulum. I also liked Jingo, Feet of Clay and Witches Abroad. And Guards! guards. And Equal Rites. So, loads of them. I love all the witch books, Nanny Ogg is my favourite character ever!