What I think would be one of the biggest problems with configurations is changing the layouts of already decorated interiors. I would assume to prevent clipping with any furniture (stairways, doorways, walls, etc popping up in the middle of stuff,) that you would only be able to change completely empty houses. Sure, you could pick up all of your stuff (that doesn't get destroyed when you retrieve it) but for bigger houses, that is a lot of bag space. Then, of course, there are the aforementioned items that can't be put back in your inventory and will need to be replaced. It certainly would be really nice to move a door or a light as needed, but I imagine it would be quite the hassle and unfortunately I really don't see square spending the time or effort on it at the moment. :/