I agree about the more advanced picture books. They cover a lot of advanced topics, in math, science, history, ,punctuation, etc. What the chapters books are good for, I find with DS6 were the areas where he is not advanced, meaning not asynchronous, like his sense of humor, some of his emotional development, the appropriateness of things he just didn't need to know how to handle. And he doesn't always want to read heavier items. I strive for a broad mix - at one point he said no more picture books, I prefer chapters, but that actually didn't last long!
DeHe