I have seen on the guild wars wiki that guild houses are planed to be released, but ever since i started playing this game i thought player housing would be a cool idea.
it could be good for both player and the game makers. By creating housing the game can make money by selling floor plans on the item shop, with different sizes and options in about 3 floor plans from 5-15 bucks. at the 5 dollar basic floor plan people can save up gold and get them for a reasonable price with out spending real money.
It can also be good for players by adding more to the experience, players can decorate and store items. By adding a new crafting profession ( i think wood working) players can create house hold items, some for decoration (bed, chairs, tables.) and some for personal use (plaques to hand weapons, cheats, or even small in house crafting stations.). these items can even help the player economy by giving new items to sell on the trading post.
Now i know the idea of placing new houses around the world would be stupid and impractical. but i have noticed in many towns there are streets and passages that lead to different decorative buildings. by using these and instancing the doors it will give them use and keep the world clean, and by doing this you can even invite your friends the same way you do story quest together, to show off and and 1 up your friends.
I know this is may not be suitable but its a building block , just a few ideas i had.