More Information for CURT MFG 11306
I installed something similar on my aveo5. I use this as my bike rack.
XPORT Flatbed 2-Bike Hitch Rack - Bike Transport
Personally I think you are going to be in an adventure trying to use the limited space for you adventure. The one thing I think you left out is food/clothing space. I personally could not fit in the back, 5'11". So when you transition from nomad to sleep, where is your clothing/food going? (forgive me if I missed different sleeping arrangements)
I have really good luck with bike rack on the back, it keeps the bikes out of the main airflow and my millage has not suffered. That bike rack is easy to get on and off.