I had an idea for when a server transfer function is finally implemented, and I thought i'd share it here.

Every month, the server with the lowest amount of players becomes open to transfers. Any player on any other server can transfer to that server free of charge.

1. Friends will be able to join up with each other if they strongly wish to.
2. Transfers won't be massive because people will become more tied to linkshells hopefully.
3. It allows transfers to be free without highly populated servers becoming even more populated.

RISKS:

1. People might make a habit of changing server every month, meaning that the "server of the month" will always be packed full to bursting and any other server will be lacking.
2. The server could be full within days, so it would boil down to getting in there before everybody else at the start of the month.
3. Other things I didn't think of but you'll probably point out.

ADDITIONAL IDEA:
A linkshell leader could apply for a linkshell transfer, and then everybody in the linkshell will be offered, either by email or in-game, a chance to move to another server.

Thanks for reading!