The issue is that individuals don't want to leave. They have free companies. They have friends.
You need a means of encouraging entire chunks to leave in a group - a whole Free Company to be willing to go to greener pastures where they have a shot at buying a house, for example. There is going to be hassle involved no matter what, but making it free turns it into a reasonable option finally.
I do agree that any free transfers would need to be to only a handful of worlds where the population is not an issue. SE has the internal data for that.
