One per data center still doesn't solve the supply problem when it's estimated there are up to 2 million active players (personally I think the number is about half that - players forget the unofficial census is for characters, not accounts).
We have 73 worlds across 9 data centers, each world with 7200 houses. That's 525,600 houses game-wide, less than the estimated number of active players and not including the number of FCs competing for those houses. Those numbers will be gradually increased to 93 worlds across 12 data centers and 669.600 houses over the next 16 months (if SE is able to keep to their tentative schedule that was announced back in January).
SE is going to continue to prioritize FCs for housing. Expect 40% of the houses to end up in FC hands. That leaves about 400,000 houses for personal use.
Depending on what you believe the current number of active accounts is, you're looking at enough houses for 20-40% of players. Give players the chance to get one house per data center and the percentage of players able to get a house drops even further as more players try to take advantage of the ability to get multiple houses. Each additional house a single player gets is one less player able to get a house at all.
If there is one million active players split evenly across all 93 worlds, SE would need to increase the number of wards (with subdivisions) per world to 180 just so every player could have a single house per account. If there are two million active players, it would require 360 wards per world.
To allow players up to 8 houses per account (keeping in mind that entry subscriptions have a limit of 8 characters), it would require 1440-2880 wards per world.
To allow players up to 12 houses per account (one per data center), it would require 2160-4320 wards per world.
And all those numbers don't include the number of houses and wards that would also need to be set aside for FC use.
It will not work. The numbers involved are too large to be sustainable using a ward system. There will always be players left out.