I revisited this discworld novel (read about the plot of Mort here) and I still love it.
As in most Pratchett novels the characters are funny and well-rounded. I still think the idea of Death talking in capital letters is hilarious, even the "anthropomorphic personification" itself is ingenious. And he/it has problems with his/its job and is not satisfied with the "life" he/it leads?! Terribly funny.
If you look more closely you can wonder why reality has to heal itself when something unexpected happens and why people only see or believe what they expect - not necessarily what is really around them. So what's reality? Life's what you make it?
There is - as usual with Pratchett's novels - more behind the funny story and characters.