Yes, #7 is pack lightly. My first trip overseas was for 30 days and only a carry-on backpack. I could have done it no other way. Wash socks/underwear in hotel sink to dry over night.
High on the list, Don't learn this lesson the hard way: learn to be safe. Keep the odds in your favor. Best advice that I read recently (which I've always followed), dress to fit in, not to stand out. Leave your American team ball cap at home (Yes, you will see natives wearing knock-offs but they look different under one than you do). Same with American flag T Shirts and the like. When someone asks me where I am from, I tell them my home state, not "America" or "US."
#8. You will learn that you should have worn high quality walking shoes if you don't have them. (Glad I read the guide book, first.)