I'll be taking a 6D and 5Dsr, plus a limited number of lenses. I need input on which to take besides the 24-105 f/4. Options: 16-35 f/4, 85 f/1.8, 70-200 f/4 or f/2.8, 100-400 II. No tripod and no speed light, and my choices have to fit in my backpack along with a 4 pound laptop. We land in Rome, and in a day and a half hop on a cruise ship. Croatia, Montenegro, Greece, etc. At present I am not planning on taking my 60D, but that is a possibility. More reach, sort of, but with the cropping capability of the 5DsR I don't see the point. In previous trips to the UK and France, while I had two bodies with me, I generally only carried the 6D and 24-105. My wife will be in a wheel chair this time, so I cannot carry the kitchen sink.