Actually, the books are quite clear that the sietch has a rather distasteful odour. When they arrive at the sietch, the fremen are happy to be there, and to smell it. It signifies home. Its purpose is to show just how harsh the survival measures are in such a place. While thats your opinion, and of course are entitled to it, I would respectfully disagree. For me, I would first of all mention a great let down would be from the Legends series. One of the biggest for me was the formation of the mentats. It felt a terribly weak introduction as to how Mentats came about. From Erasmus? The Bene Gesserit are a whole 'nother animal from what I was expecting, too. To go to Sandworms, I can't really think of a redeeming feature. At all.