As many people here know, Southwest is the first low cost airline in the world. So I would not say its history here, and would only discuss its special inflight service policies.
Southwest recently changed the policy of obesity travel, so obese passengers have to buy 2 seats on travelling. This caused many complaints, because obese passengers are considered as disabled passengers on other airlines, and they can get special assistance like sitting on 2 seats without extra charge.
Southwest is the only airline in the world installing backward-facing passenger seats near the emergency exit. Such design makes best usage of space because on single aisle aircrafts of other airlines the row near to emergency exit has to be made to much wider seat pitch for passenger access, as well for disposing of window exit. But I think this design is not good, as this prevents passenger to extend their feet to the space below the front seat. This also makes passengers sitting on backward-facing seats cannot recline at all.
So I think it is much better to cancel the window seats of the window exit rows, so allowing removal of window exits without causing problems of backward-facing passenger seats.