Okay, these are my opinion. Some people, maybe many, might disagree.
Vietnam. Maybe you’re a vet and would like to go back and check the place out again. Go ahead. Just remember that the prevailing philosophy of the communist countries in that part of the world is to Fleece the Rich American. You’re best off in a group, and it’s not as cheap as, say, Indonesia. Vietnam is working on improving its tourist image and skills, and they’ve come a long way, but they have a long way to go.
Cambodia. Improving, but still too poor to offer much. The cities are, crowded and uncomfortable, and if you get out in the countryside, watch out for land mines. They have done a lot of work on their roads, and I recommend you stay on them. The country was hurt pretty badly in the Vietnam war era, and they are still recovering.
They do have Angkor Wat, which is spectacular enough to justify a trip. Be careful of the surrounding area, though. Mostly slipshod development.
Philippines. Unless you’re going back to visit relatives, you will find lots better places to visit. About every human-occupied place is full of trash—they don’t clean up very well. The government and lack of “peacefulness” in the culture aren’t super good for tourists. Beware of the food and water. Not much gourmet food here. Not much in the line of historical buildings, either. Here’s the first word in a text box on their official tourism site: “Pursuant…” Friendly, eh?
Underwater adventures are okay, though. The hill country in the northern part of Luzon with all those rice terraces isn’t bad. If you like to sail among islands, you’ll find more than 7000 of them to sail around. Not all the natives are friendly, though. One good thing about the populated areas: the educated folks pretty much all speak good English. I get a lot of customer service agents with Philippine accents. They’re easier for me to understand than the folks from India.
Burma. Oops, Myanmar. Forget the shave. Oppressive, unfriendly government. Poverty. Go someplace else.
Enough gloom and doom. Nice places next time.