I survived a trip to Krabi with 3 lenses. 11-16mm, 28-75mm, 70-300mm. It's all about planning. When u are with a group for walk abt, you tend to shoot more of people and things on the street, hence I kept my 28-75mm on while having my 70-300mm ready. When it's time for scenery, it's 11-16mm with 28-75mm as backup in case I want to isolate the subject. Going out of the country is not a common thing for me. I rather bring all than missing shots. On top of those, I'd a external flash and tripod on my bag almost all the time.
wow, kind of heavy load. but one thing i scare is carry too much things scare will get damage, like knocking here and there.