Blizzard has been trying to make free transfers work for years and it hasn't worked yet, for a pretty obvious reason. I'll just repost the post I made on another thread.

Square Enix needs to offer incentives for entire communities to transfer, not just individuals.

An RP designation on a new server is one such incentive that would encourage an entire community to transfer.

MMOs are social games. They are built and sustained around communities. The idea that gil and chocobo feathers and less queue times are enough incentive fails to acknowledge this fact. If you're an individual or solo player, then hell yeah, those incentives are great! But for anything more than an individual player or a player with a small group of friends, they're wholly inadequate.