The first three items are really personal and often each person may have a completely difference idea as to what to bring. The fourth (food) is really a question mark for me. With all of the research I did before leaving for Greece I had the hardest time finding out if I should bring anything edible with me. If you ask people who've visited, in my case Greece, you'll find that you get many comments about restaurants and nothing about groceries. You'd think Greek Canadians would be the best help, but frankly I got mixed messaged from them.
So here's why I think Greek Canadians couldn't help me. In Canada we have a huge selection of foods to choose from, the US is pretty much the only place I've ever been with a larger variety. I'm not saying our food is better, there's just a gigantic variety. So people that move from one country, say Greece, will often find all of the foods that they enjoyed at home in the stores and some. However the opposite is not always true. In Greece for example maple syrup is pretty much an unknown item, olive oil is everywhere, however sesame oil is scarce. Many spices are also hard to find, even though saffron is sold by the kilo, and cheap.
I'm not putting the food selection of Greece down by any respect at all, I'm just saying that getting a comparative list of foods that are available all over the world would be great, however I think it might also be impossible.