My husband and I often traveled but to countries whose 2nd language was atleast our 1st one. This meant we could aways find a way to communicate. However, our most recent major travel we arrived in a country whose 2nd language we did not speak. This brought a huge host of challenges. We had to use dictionaries alot. Have you ever done this? What did you do to get by?
The last country I visited was Singapore and thankfully most of the people there speak great English. Wherever you go, people are capable of conversing in the language. Now I'm planning to travel to other Southeast Asian countries - Vietnam, Cambodia, Laos, Indonesia, Thailand and Myanmar - and they obviously cannot converse well in English compared to my native country, Malaysia and Singapore, the known English speakers. It's going to be a tough one that's why I think I'll book a tour instead or befriend a native who's well-versed in the universal language.
It depends on what type of person you are, because you know you can get by by learning some phrases and taking a dictionary with you and preparing and figuring out what you need to say. That separates a traveler from a tourist who may not want to learn and hopes everything is in English. I have been in many countries where English is not spoken and I get by because of the person I am.
If it helps, some of my relatives just came back from 3 months in Thailand and they said that Phuket had many English speakers. But I think that was tourists like them and not local people. They did struggle with the language but loved the experience. They said they had to be aware of local customs though and try not to disrespect them. It sounds like you are pretty well traveled though so already know how to research that before hand. Have a great trip!
I've been in places were I couldn't speak the local language. Normally though all you have to do is ask anyone you meet if they speak English and once you find one you strike up a friendship [with them]. In some countries where the natives are unfriendly this might not help much. So much as you can get by with a few phrases, it's advisable to take along your language guide-book just in case.
I have not traveled to any where outside of the states. I do plan to go to France next spring and will need to brush up on my French. I took French in school that was 100 years ago. I also need to brush up on my spanish as I want to go to Cancun soon.