@mission_bug
As Vietnam is my home country, and I have seen it countless times from above (not from the air, but there are lots of mountains and hills in Vietnam), I feel that's my responsibility to help you finishing your excellent map. Unfortunately, I don't have much time (due to my work), so my help is quite limited at the moment. Nevertherless, I try to write down a short "review" of your WIP map. Hope it helps.
1. I have the feeling that Saigon is your start point, so it's logical to start first at it. WOW is everything I can say. I always had fear that someone will mix it up with a Chinese town, but no, it looks exactly like it should. The scale is somewhat small now, but I don't think it's a big issue. The motif is excellent. My only suggestion is: it would be even better if you can place the presidental palace on the map. It's one of the most important place in Saigon and was the theather for many important events of vietnamese history: the Ngo Dinh Diem's assassination attempt using Skyraider, the attack in 1968 legendary offensive, the secondary bombing in 1975... to name a few.There would be no need of new building, just a large place surround by fence (and please, not Gestapo's labour camp fence

). Doesn't need to be 100% realistic. Just an unique place in Saigon which differs itself from every other buildings.
2. The map's texture is somewhat low on quality (Google Earth doesn't seem to be the best solution), and it's way to dark. It's OK on forest and mountain areas, but the Mekong delta should be brighter. As I said, I'm quite satified with the mountain areas and the airfields. The following pic (your pic BTW):

is excellent. Very realistic.
This one (taken over a paddie fileld)

needs to be fixed. The paddie field texture is completely wrong. Take a look at this

Of course, the color of rice changes during its life circle, but take into account that most of time it's green, I think it's safe to assume that it's green all the time. And the paddie field is nothing like field in Europe. It's vast. Vietnamese often says: the paddie field is so big that the storch can't fly from this end to the other. I've flown many times from Europe to Vietnam and back. When you land in Vietnam, you only see a big big big screen of green. Tan
Take into account that Mekong delta produces most of rice in Vietnam, the appropriate motif should be: big city and smaller villages almost "sinking" in the giant sea of green paddie fields. There aren't many trees on the field, but in constrast, a whole bunch in every villages.
3. The map is still very little populated (I know, it's a WIP). Most of Vietnamese people live at the villages, so they're as important as cities. As I said above, there are many trees at the villages. And remember, many many villages are on the two banks of the river (a very specific feature of south vietnamese villages). The cities in contrast have much less tree. The motif of Saigon will pass very well, but with smaller houses (one-story).
4. The sea coast is a very different region: smaller and seperated paddie fields, many villages on the shore lines. The cities should be the same.
5. Some names are misspelled, but I'm now too busy to make a complete list.
As I said, I don't have too much time to discover your map, so if something is wrong, don't bear any ill will
