Maybe the world does have enough sequels, but good characters are tough to create. I mean, I don't think Harry Potter (it was only a matter of time before he popped up in YA fiction discussion, eh?) was a particularly good character. A character in an interesting setting with an interesting back story, but as an actual character, I think that Timothy Hunter from Neil Gaiman's The Books of Magic is a much better character. He's darker, he's more human and more flawed. Both characters have a certain darkness and temptations of power and fame exist for both, but Timothy Hunter is painted much more vividly. I think seeing Sam progress into . . . wherever could be fruitful, especially if as mk said, ". . . that sinister nature of Radium Baby were turned up a notch or two". There's a lot of room to play with character arcs and characterization in a world with cannibal bishops, mad, gibbering financial geniuses strapped to boards and radio contests that willfully endanger the lives of minors for advertising revenue, no? I dunno, it seems to me that if I created a universe I'd want to find out what's hiding in its fundamental fabric.