My usual commute to work is like eight miles. I've considered purchasing an old leaf just to use to drive to work and back. The fact that they only get 40-100 mi round trip is negligible to the fact that I would save a decent amount of money on gas.
The trade-off turned out to be that my insurance rates and the other maintenance would more than absorb the cost savings from any gas so unless I also got rid of my primary vehicle which I'm not likely to do it would be a bad move for me.
How is your insulation between your ceiling and the roof?
A radiant barrier helps but it's not going to be a match for fully functioning r22 batting or anything.
And you might want to consider replanting shade trees now that the old ones have been removed. Once it's the same height as your house it puts out as much equivalent cooling as a window air conditioner, and during the summer that's money in your bank.
And honestly, since you live in Texas and you're paying $285 a month for electricity, looking into some sort of solar might be well worth it.
If you have a larger property like my dad did down near Austin, you could probably do a ground mounted solar install and save a lot of money on the installation which is where with current rates the majority of the costs go to installing solar.