Lens help for mediterranean cruise??
I live in the Mediterranean region and I strongly advise you to take wide lens with you! Old cityes in the Mediterranean have narrow strets, some big squares & big publich buildings. For all of them you will need wide angle lense. If you want to capture some deatails than you have to take some telephoto lens with you as well. Also, I wouldn't recoment taking with you more than two lenses... From the listed combinations I would recomend you , but without Sigma 30 i.e. Canon 15-85 + 55-250.
Personally, If I travel alone I take with me 6D, TS-17mm & EF 17-40mm and G1X. If I'm not traveling alone (read there is a victim for carrying equipment), then I take second body 5D MK II and EF 100-400. How these combinations work you can view on my web site.