I am at the top tier with Princess so this cruise was purely based on the itinerary. I found myself comparing everything with my experience on Princess ships..
However, Nagasaki, Jeju Island , Busan were places that , if not visited, wouldn't be such a big deal. Beijing, Taipei, Seoul were great as was the end port Shanghai.
Would have liked an overnight in Seoul instead of Busan or Jeju Island. lots to see and do in Seoul as a day trip was too rushed as the port is a few hrs drive.