This might not work for the ladies but pack half the Clothes and Twice the money !!! ( more room for shopping.)
If travelling as a couple with two suitcases always mix your belongings with each others ,,, just in case one case goes missing
Always take a photo copy of your passport and keep it in a seperate lace
A travel adaptor and your mobile charger
A small torch
Rehydration sachets and a couple of emergency plasters