Just a small tip coming from a Customer Service background. Break the letter down some. If it is 1,000+ Words the entire letter is not usually read. Only put the points you are trying to make and make it less of a sob story and more what went wrong. Just a little tip. Also in the letter clearly state what you want from Delta. When I worked for customer service for another company (not stating name) if the customer did not put what they wanted we would give them a standardized compensation.