"One dimentional"
How weak and unplausable the characters and plot was.
Based the story in a more realistic plot. Not make us want to sympathise with characters that are richer and more beautiful than his readers. Not make us want to feel anything for a murderer, a narcicist, a (un-fleshed out) rich antagonist. make a stronger case for bring "driver and Panter" into the story.
He gave each character personality even though the characters, as written, had no depth.
It was the cutting that destroyed the novel. There was not enough back story and motivation to drive each character to the extreme behavior they exibited.
After reading the Gidion series I was waiting and dying for book 5, Not any more if he is just going to phone it in.