Shawn, in my biased opinion east Texas has a lot of advantages for a pond guy.
First and most important, it has more precipitation than west Texas. Given the typical hot, dry summers we have here, plentiful water the rest of the year is essential. Unless you plan to drill a well & probably have to treat the well water, an expensive proposition, east Texas is best. The further east, the more rain, right up to the Louisiana border.
Second, fish suppliers and pond consultants are more numerous in east Texas than west. That's mostly due to the fact that there are lot more ponds here, which in turn is due to reason number one.
Third, you have a ton of fellow pondmeisters in east Texas. Their advice & assistance can be invaluable at times.
Fourth, it's easier to hide your pond behind trees when there are trees, especially pines!