I am not a lawyer yet, but I am in law school so I will offer my two cents as I went through the decision not that long ago and am currently going through the job search process. I would go to Texas. It has a great national reputation. This option would probably give you the most flexibility in terms of search area for jobs right out of law school.
I don't know if you would like to live permanently in any of the areas that you have mentioned, but Texas will give you the greatest shot of finding a job right out of law school outside the general region of the school itself. I am not sure abouct UC Davis, but there is a greater chance that if you went to William and Mary, you would end up practicing somewhere in the Virginia, North Carolina, Washington D.C. area. Also, even though there are a number of law schools in Texas, there is a great deal of competition for legal jobs in the area of William and Mary. In that general area of Vriginia, you have the University of Richmond, University of Richmond, and if you go a little farther north you have American University, George Mason, and all of the other schools in the D.C. area.
That said, if you feel that you would be a great fit at any of these schools, I would recommend going to that one. It is a three year experience and if you go to a school that has the best reputation but that you personally do not care for, it will be a long 3 years.
Also, Austin is a great place to live.
ETA: This is not to say that the other schools are not good, just out of those three options, Texas has the best national reputation.