And upstairs looking back toward the rear of the house:
We added the living area on the second floor where the TV is during the remodeling before we moved in. It was a good use of the open space that existed and still left us with an open ceiling. It is a great place to hang out. We stoned the chiney inside and added a ventless fireplace with propane logs.
Hard-wired smoke and heat detectors are a must. If I was building new it would have a residential sprinkler system.
The big vent at the top of the ceiling is great for re-circulating hot air back through the air conditioning vents.
I hope they can help you with some ideas for the Nature Preserve Lodge.