There are already at least a few of these maps, why do you need more? You can't have possibly used these to their full potential.
The ones we have a huge. They don't have many detailed building interiors because it would be laggy and hard to design to begin with.
I think you've made the best point though Aes. The maps would take hours, if not days / weeks to complete. Its not worth it since v21 is on its way.