Okay, I've taken some time to think it out. It's true you'd need a BIG carrot to get people to transfer whole FCs onto less populated servers. There would be several advantages if you did, obviously:

-FCs would have more fruitful recruiting grounds, and those people would have hopefully more experienced folks to play with
-We wouldn't have so much server packing going on, meaning people won't leave the game after playing alone without knowing how much is going on outside
-It would solve about a hundred housing problems, hopefully. It would probably be the best help for housing short of simply introducing instanced housing.

However, there would be drawbacks for the FCs and players leaving to these "recommended" servers:

-We're talking about these people moving to much lower population servers, where people are meant to see lots of friends around.
-The market boards inevitably suffer on smaller servers where lack of availability drives up prices (if you can get what you need at all).
-Players will have to make all new friends if they didn't transfer with them.

So, the idea is to introduce a system whereby a player (or an entire FC of players) can take a transfer to a server of somewhat lower population. The system would work like this:

-In the case of a single player, a player from certain high-population servers can move to a set of certain lower population servers (I recommend not being the dead ones, but the ones SE is attempting to "build up" to compete). This triggers a rename if a player on that server already has it (though, obviously, they're moving there because there aren't a lot of players).

-Certain servers are deemed to be "building". Those servers are marked as having enough population to be stable, but require more players. Other servers are deemed to be "at the ceiling" and are having trouble with high populations and housing. An option is then included so that players and FCs from the "ceiling" servers can elect to move to the "building" servers for a bevy of enticements and the advantages of being on one.

-In the case of an entire Free Company, the FC leader can elect to shift servers and the Free Company comes with it (triggering a rename if another FC with that name already exists). Every player in that FC, next time they log in, are automatically given the choice to jump to that server.

-In these cases, a mail is sent to everyone in the player's friend list to let them know that the player transferred using this system (and inviting them to do likewise).

To make this enticing, beyond the few advantages of being on a lower population server, and to somewhat overcome the problems of lower population servers (dat gilspam), I recommend the following:

-Market Boards should "merge" as they must to maintain better flow of goods. Either all the market boards in a datacenter could be merged into singular market boards, or a more flexible system grouping smaller market boards together until they're big enough to stand on their own can be built.

-Of course, Duty Finder queues should be as broad as possible and connect as many servers as possible, but SE already seems like they're on that. Definitely, though, they should use this system to balance datacenters if those are lopsided as well.

-Though you cannot "transfer" property, the entirety of your house's (and your FC's house's) inventory of goods can be stowed in an original, unbound condition (so you can sell them or use them on arrival).

-Nothing is lost in the transfer. Though your servers you can pick from are limited (that's the idea of getting people onto lower-pop servers), there are no limits on what comes with you. All your money, all your items, all your retainers, everything just moves with you. A voucher is given to every player that takes it to get a personal room in a new FC house, and the FC leader will get a voucher for a workshop and all their associated Airships.

-Players who elect to take this transfer can, after some time being active on the new server, get a set of items that persist for as long as they stay on the server. This would almost certainly include a two-person mount, but also minions, costumes, etc. A pretty decent package, all told, would be advisable. FCs that elect to take the move will also get some bonuses for themselves. These items may become permanent after a period of, let's say, six months on the server.

-In the case of the players, they will get a non-gil currency bonus for a series of six months (depending, it may be permanent) of amounts like an additional 10% or some such. So you get extra esoterics, lore, etc. That will help compensate those players for the lack of immediate friends. FCs will get the same bonuses in the form of company seals.

-An advertisement message pops into the general chat when one of these FCs shows up, letting people know that a Free Company has arrived on their server and has affected their name change. That way, prospective members know where to look.

-In the specific case of an FC or player transferring who own a FC or personal house, a "reserve list" is put together. The "reserve list" can include their particular size and/or zone, maybe even specific lot (though that may be problematic). It holds money at the LOWEST value of the property in escrow. As soon as a house comes available meeting those specifications, the player (or FC leader) is told where it is. It does not enter the market. They may then go and use their escrow to purchase that property (recall, at the lowest possible price instead of the starting price), or they can release their escrow into their inventory or the FC bank. They can, at any time, change the parameters of their waiting list to be more inclusive. If a house is already available with the beginning parameters, it is immediately reserved and can be bought. It does NOT have to be the same size as their current house; they only need to have enough money to put in escrow to cover it.

-Of course, a player transferring with his FC would be treated as if he were personally transferring (he technically is). At the same time, a player who chooses not to transfer with the FC does not receive the benefits, but he is not FORCED to move.

This system would also have certain requirements to use:

-A player would have to have at least one character of level 60 (50 if we're feeling generous) and would have to have been on that server for a total of six months beforehand. The only difference is if a player is in an FC that is transferring. Speaking of...

-A FC would have to have at least seven members active in the last 45 days that would qualify for the transfer, be six months on the server, and be rank 8 (rank 6 if we're being generous). Seven members MUST transfer before the FC receives their bonuses. If seven members do NOT transfer, the transfer takes place but the benefits, including the housing reserve, are essentially frozen until they do.

-Players who transfer with an FC, but who would not otherwise meet the conditions to receive bonuses, must remain with that FC to keep their personal benefits for six months.

-Server transfers of any kind are disabled for any of those players (and FCs, for what that's worth) for six months after that transfer.

Any additional feedback is appreciated, especially additional carrots we could use to incentivize movement.