coming from the Philipppines and having lived as an English teacher in Bangkok and Hanoi, I am certain you will have better job prospects from international schools in Hanoi and BKK and not in PH. Hanoi offers higher pay and better benefits like free tuition for your child if you are a teacher in that school (from legit international schools and not billingual ones) In terms of overall livability factors, I prefer BKK but I've chosen to stay longer in Hanoi due to its monetary incentives.