I don't think it makes a great deal of never mind. What is more important is - has the seat got sufficient stuffing to be comfortable? The width and pitch will do far more to affect comfort and leather is just a marketing gimmick, in my view.
As to what would I want to see then the answer is simple: Appropriate value for money. If I pay the base fee, then I want to get a decent seat and service. If I pay 50% more then it should be (nominally) 50% better. Too often hotels and airlines promote a premium product and do not present the goods.