A few years ago American Airlines lost all of my wifes luggage. None of mine or the kids, just hers. We booked the flight on our own and not thru RCI.
However, the RCI folks were outstanding! They were more than generous offering my wife outfits, dry cleaning services free of charge, plus a few other minor things. We had zero cooperation from the airline, they clearly gave a rats-a--. In short, for us anyway RCI's customer service was superb & is always a primary consideration when we book a cruise. As you said, they aren't cheap & you have high expectations.