You are lucky to have a reader who likes to read! Our DS6 was always a sneaky reader, and it's rare that he wants to read to us or for long by himself. He has tested very high with his reading skills, but he's always preferred us reading to him. I have caught him reading Geronimo Stilton chapter books. These are fun chapter books with lots of pictures and different fonts. He also likes the DK readers, which have several levels and topics of interest (DS likes Star Wars).
As an aside, he told me a couple of weeks ago that he hates reading aloud, since it takes too long. He prefers to read silently to himself.
