I think para 6 sums up one of the key factors - Access. To markets, to services - and everything else it entails. E.g.: people who can access government services and education have a better chance of getting a job abroad - then their families have a better chance of accessing their remittances, and climbing another step up the ladder. It's not the one answer, but I submit that getting the basic pathways to access right, and knowing when to get out of the way and start spending elsewhere as citizens take over, deserves a lot of priority.