I finally looked at the Evantil house and I was shocked how big it is. You can basically construct a mansion with construction pieces in there (and edit exported layout data to make the pieces line up properly on import). Some of those pieces are big enough it "only" takes about 10 of them to make a floor in the upper portion. That's a good idea either way since that house exists. I have no idea how it compares in size to the others.