Of course I am.
The Colour of Magic and
The Light Fantastic need to be read before you can read
Interesting Times, otherwise the history between the characters is missing. And
Equal Rites is a good introduction to Witches, and how they opperate as opposed to Wizards.
The way I see it, the development of various characters has been both good and bad for Pratchet. Susan Sto Helit and Samuel Vimes have both reached momentous occasions in their lives recently (Susan has a possible love interest, Vimes a son). This presents an author with myriad opportunities.
On the other hand, Granny Weatherwax and Rincewind hav both been written into corners. Granny has defeated Vampyres, Elves, Foreigners, Pretenders to the Throne of Lancre, Phantoms of the Opera and her own sister. She has sent her consciousness into an eagle, an owl, a stag, a University, a swarm of bees and her own blood. What else is there for her to do?
And Rincewind has finally found a nice, safe job, and recognition as a Wizard by UU. Sending him on a dangerous adventure woudn't just be cruel, but also very coincidental.
No wonder Pratchet likes the Watch so much.
Sum sui generis
Vs