księżycowy wrote:I'm not sure it's necessary to add in the first place, but I think a native's input would be helpful.
There's no "correct" answer to this flag question. Different people coming from different backgrounds think differently about it, whether you poll the ones from Vietnam or the ones overseas. Both the regime sympathisers and the anti-regime objectors think their choice of flag is the only legitimate, and start flinging the lowest of insults at the other side the moment they come into contact on the Internet.
Personally I don't associate my native language with any flag at all, but maybe you can try to simultaneously appease and spite both groups by going with a half-and-half vertical composite flag, I don't know. When it comes to representing Vietnamese people/culture/language, it's best to stay away from this issue and only use some imagery that both sides can agree on (the "Viet bird" on a bronze drum, lotus flower, farmers wearing conical hats working on a rice field, water buffalo with boy riding it, some famous Vietnamese painting, or whathaveyou). Probably too much nuance for a forum like this though.