Also, just put up a photo of the hub for stacking two full miniplanes, and updated prices for bare boards. 1-5 for $25 each, 5+ for $20 each.

That is an aeroplane :p
What is the advantage of doing so? Thou I don't have that much of boards

Someone can correct me if I'm wrong, but it just makes connecting things simpler. You don't needs separate internet connections and power for each board, you centrally plug them all in to the hub.
IAS