The Miocene Arrow is an improvement over Souls in the Great Machine, but the characters are still more like pawns for the author than real people, although there's a lot less sudden madness and changes of motivation.

The plot is more controlled as well. There's no last-minute introductions of major plot elements, and it all hangs together reasonably well.

Still, I was starting to get tired of this author towards the end of the book. Stay tuned for book three.