We were just like that D&C. DS7 could never tolerate a whole series - usually 2-4 books from a series. The most of any one series he did was Geronimo Stilton, although I'm sure he didn't come close to finishing even that one.
DS actually loves graphic novels and long comics (adult-ish). At 7, I think it still appeals to the part of him that would like to read picture books. A lot of them he picks up actually have good portions of text and probably at least a 6th grade reading level. Right now he's reading vintage richie rich and re-reading a graphic novel series on the life of the Buddha (which is actually very adult).
