I really, really, really liked Jeb. He was, I believe, the most 3D character she has ever written. While Twilight was her first novel and filled with unbelievable fairytale vampire creatures who were perfectly cardboard in every way, The Host really showed just how many different types of characters she could make.
While she seemed reluctant to give the main characters any believable flaws, I always find the side characters very entertaining.
Jeb was by far the best. His humor, his sarcasm, his gruff attitude, but the pure kindness inside... Yeah, he was pretty amazing.