Folks keep bringing up Instanced Housing like it would be some miracle cure-all when, in fact, it would remove one of the biggest charm points about the housing system as it exists now: The ability to show off. Apart from gardening, showing off is pretty much the entire point of personal housing. You want people to see the homes you've built and decorated with your various trophies and adornments. You can't do that with instanced housing; you're the only one who can see it, unless there's some method for visiting another person's house in which case likely only your friends will ever bother.

Housing was instanced in FFXI. There were all kinds of furnishings and decorations you could put into your personal house, and it all felt terribly, terribly meaningless. Even after they added the ability to invite party members into your home, folks seldom did so and, at any rate, it's a lot more fun to impress a stranger than to impress a friend who already knows and respects you.

Instanced housing will fix one problem (housing shortage) and replace it with another (lose the fun of showing off your house). A decay system, where inactive homes are eventually released will also not solve the housing shortage problem to any meaningful degree, but it WILL solve another problem: Wards becoming ghost towns. The majority of players leave the game eventually, many without any intention of ever returning. Cleaning up the houses of folks who've left the game is something that should be done, so we don't wind up with wards full of houses but with only one or two active players there. It's not about the shortage - it's about keeping the wards alive with active players.

Tying house preservation to your subscription seems like a fair solution to me; if you value your home and think (or KNOW) you'll be coming back to the game someday, just keep paying your subscription. The fact that you're paying real money indicates that you're serious, both in your intent to eventually return and in your devotion to your home.

Someone brought up the point that hey, if you're gonna take their house, why not take all their gil and possessions as well? The problem is that your gil and possessions are not an active part of the game unless you're actually playing. Your house IS, whether you're playing or not. When you log off for the night, your house doesn't disappear. It's still there, anyone can visit in in the wards and even enter it if that's how you've set your permissions. When a player leaves the game, it's no problem for SE to make a record of their character and shove it into some dusty vault, never to see the light of day again unless you happen to resubscribe, in which case SE can dust it off and put it back into action.