My barn has half walls in the interior, except for the tack room of course. The top half of the walls are pipe. I'm fortunate that I have no humidity here so just being in the shade is cooler, but I run fans in the summer time about a third of the time.
You definately have more heat than we do ;~D
I hope to find property with lots of shade, and I would not be taking every tree off the place, but rather trying to leave as much shade around the grounds as possible. I am ~not~ heat tolerant.