As Beth indicates, I will be on this one as a segment in the full circumnavigation, and am certainly looking forward to it. It will be great to be back with the group.
I also recommend Machu Picchu. Susan Walsh had worked with Ker & Downey to put together our trip, and I do recommend you look into that approach. She also did the same for our side trip to Angkor Wat from our Pacific Rim cruise earlier this year. We paid $500 per person less than the ship's tour (the ship was Crystal Serenity), and had what appears to be a much better experience. We had one guide for two of us, rather than one for 20+, and he knew the ins and outs of how to dodge crowds and extreme heat, and yet see the complex in a way that was just spectacular. Same thing with Machu Picchu (though for that it wasn't really from a cruise, though we went there right after a Silver Galapagos cruise).
Anyway, I look forward to seeing everyone.