Geez, bunch of lab guys or what! Great dogs, but don't fit the criteria. Personally, I would not want to leave a lab for 9 hrs a day, either - at least not one younger than about TEN! Active doesn't begin to describe them. They are gentle to a fault, however, and great family dogs for the right circumstances.
I can second the newf recommendation too, as I grew up with them. Big, drooly, and shed mountains of hair, though.
Two mentioned that do fit your criteria are the Airedale and Aus. shepherd. In other directions, consider the basset hound, ENGLISH bulldog, and the Bernese mountain dog.