Here are a couple answers to the above questions as I am an ASA pilot also contemplating the move.
As far as I know, the upper management is all Vietnam locals except for the VP(?) of Flight Operations--who is the former Director of Safety at ASA--and the VP(?) of Maintenance (also an ASA MX manager); have taken this as a promotion and are already over there.
The ASA mechanics are being offered a similar package and there will probably be a few that go. Flight attendants will be locals, pilots will all be ASA pilots--at least initially.
Personally I am lukewarm about this proposition. As a current FO I would love to go in the left seat, but they aren't even offering that. Only current captains can go as captains and current FOs can go as FOs. This is to reduce training cost. I have read about the long drive to Hanoi airport and worry about that as well. I think a lot of people have dreams of living in the middle of the city...if the trips are mostly day lines as is rumored this will be hard.
Anyone else with insight into Vietnam living would be appreciated. Myself and my buddies considering the move are all late 20s and single, a couple with girlfriends that would come. Thanks again.