I forget how high the sun can get down there in the summer. (Left home in 1963).
When I was kid in Del Rio, 'east Texas' was anything east of Uvalde (like Hondo).
I did spend some time on a farm near Prairie Dell. Off the east side of 35. Nice flat area..
30 deg looks like the better of the two choices.
If there is a season when you will need more power during the day time,
(like boiling hot summers) you might want to favor the appropriate seasonal angle.
Here's another link for you.
It's a pretty good site for solar stuff. They get into a lot of systems detail.
Some of it's too much for me. I just want to set-n-ferget.
Panel Angles
Here's a pic of me in the backyard..
http://i46.photobucket.com/albums/f1...solarfarm2.jpg
I'm doing an experiment, called
"Where in the world, is the worse place to mount PV?"..
For good cooling (and heating), inverter type mini-splits are only way to go.
Check them out at
Geothermal & Heat Pumps - EcoRenovator
I've been having pretty good luck with a couple of old Sanyos..