Pilots for VNA don't really have a choice, the pilot base is in Hochiminh City, the hot spots include Phu My Hung (Dist 7), an all new area with close proximity to Intl. schools, a French hospital and lots of restaurants, also close to Dist 1, another hot spot is An Phu(Dist 2 & 9) which has a lot of new housing and also close to schools. Most families are in those two main locations.
In Hanoi I have a friend in the luxury Villas at Hanoi Ciputra, a very impressive village near West Lake, security guards on all main corners throughout the village and strategically located between Hanoi and the airport.
Good luck, D.L.