Several things happened to not give this cruise a higher score

I have heard this complaint before about promised ship board credit that was not received.  Make copies of everything that you are supposed to receive.  We ask our TA to put all this in an email to us and check our statement early on to make sure that it get put into our account.  We have never had this problem.  I think it is the fault of the site where you booked rather than the cruise line.   use a reputable TA next time. 

That is very interesting. We sail a lot but with only three lines, Regent, Princess and HAL. As of late Regent has gotten very $$$$$ and HAL has developed a problem where they are the only game in town for balcony smokers. So we are using Princess. Unfortunately, up until our last voyage, on the Coral in January, the Main Dining Room on Princess was still tolerable, this time though, either we experienced a fluke or cost cutting has caught up with Princess rendering their product in the MDR undesirable for us. We have never ran into a situation like this before even though the "hand writing was on the wall" that it was bound to come. In my opinion this results from understaffing of both service and kitchen personnel. Each time we tried to use the MDR we were told there was a 40 minute wait time. They gave us a pager, but on the three occasions we decided to carry on and eat in the MDR the wait was only 10-15 minutes, which was not a problem. The problems began after we got in. 

We don't like traditional seating for a variety of reasons which I won't go into. It seemed though that the MDR service might have been slightly better if we had been using traditional. When we did use the MDR we went "anytime" and sat waiting and watching a harried flurry of activity by the understaffed help forging a losing battle trying to keep up. Made dressing up in my tux on formal nights and trying to dine there a joke. So, in order to continue enjoying the cruise we made do, by booking dinner in one of the excellent specialty restaurants on board whenever we felt inclined to really enjoy dinner or simply going up to the Horizon Court buffet.

I have a theory that there will be a drift completely away from providing MDR service on the major cruise lines in the future. Instead cruisers will experience more of and larger specialty extra charge venues and expanded no extra charge buffet area service. Did your poor dining experiences on the Crown involve more than just the MDR? Were you using traditional?  
 

We talked to Autumn Strand, our TA, multiple times, the credit was even on initial paperwork.  The excursion was a Princess excursion.  I feel that means they endorse it, they called it a 30 minute Catamaran cruise to a remote island where you could relax.  You could purchase chairs and umbrellas.  It was not a "cruise" they took us about 300 yards from cruise ship, no island it was a peninsula, RV park on the beach they took us too with tons of vendors hounding you on the beach,  20 chairs for 100 people, 4 tents, no umbrellas.  Had an open bar that was not mentioned on description, which would have explained higher price, we don't drink so would not have chosen this excursion.

Question.

Did you book entirely on line? Your TA should have been able to verify the on board credits. Also, I believe there is fine print in the excursion documents that absolve the cruise line of any trouble or failure of the excursion operator. I have encountered that myself. While not very fair, I think it is the norm.

As mentioned before in this forum, please write a letter to the customer service dept. of the cruise line and explain the frustrations and difficulties you encountered. You might get  response to the inquiry. I know that I have done this and have been satisfied with the result.