Minecraft is fun because you can build whatever you can imagine in an awesome random generated world. Huge underground cavern complete with a lava death trap? Check. Castle built in the sky with huge waterfalls reaching to the ground? Check. Obviously there are some limitations but for the most part if you can imagine an inanimate structure you can build it. This adds unique elements to the game, not everything looks the same.
From what I hear Loftar is already working on a new map generator. Adding the ability to customize buildings is way beyond the current scope of HnH. But adding other ways to customize your character and village would be a good thing. The different hair styles was a nice touch, and seem to receive a good response.