I dont see the problem with empty houses... There all part of the experience, in zelda not every house has a purpose... not every house should have a purpose... What your asking for is a fair bit of work and as a result no new gameplay is being produced, its just all same old. I suggest you give making a playerworld a crack and you'll soon discover how much of a task it is. I know from my past experience at building my own playerworld with a friend.