Thanks all for the great suggestions. We added another day from the beginning of our trip to spend more time in Cuzco/MP/Sacred Valley.

As for driving, your replies led us to reconsider the bus. My wife is a great navigator, I'm a native LA boy and am used to the stereotypical Italian driver (my wife), having driven in Rome & all over Southern Italy, but I think we're busing it Lima-Paracas. The loss of freedom from taking the bus may be well worth it to avoid the headaches if we were to be involved in a traffic accident in a Spanish speaking country. Hablamos un poco espanol, but not enough to deal with another driver and local officials.