Perhaps a good way to help a bit with the server population problem:

1) SE makes new servers, or select lowest populated servers.

2) SE Gives people the option to transfer to those low populated servers for free.

If this kind of service is offered to players, I am sure many people would transfer.
Some people want to play with their friends, no matter the server. Some just wouldn't mind transferring.
I am sure this wouldn't completely fix the issue, but it might help a bit.

What do you folks think?