People read contracts when things start to go bad. Usually by then, it's too late. It sounds like you got the Seller to repair some things, but they balked at doing additional lender required repairs. Negotiations are usually better than law suits.
If your agent is a skilled negotiator, you might ask him or her to find out from the listing agent exactly what the Seller wants and will agree to do, then see if you can reach a reasonable agreement. It is very true that most contracts have specific remedies for default, but the courts sometimes grant Buyers wide latitude in Texas. If you have to hire a lawyer, get a good Board-certified Real Estate attorney who is also a good negotiator, and see if he or she can get this deal done first, before suing. You'll get the house you want, the Seller will get the money they want, and you'll all save a lot of wasted time, money and emotion.
Call us if you need a reference to a good attorney.