Having done quite a few repositioning cruises with Royal (mainly transatlantic / never transpacific). I actually feel they tend to up the entertainment.
Every day there will be a full schedule of events as a normal cruise. There of course is sometimes where there hasn’t been something on that we were interested in - so we grab breakfast / lunch / snack or have a coffee during those times.
Some things that generally happen - that don’t always make a standard cruise with port intensive schedules - are progressive trivia, learn a dance (such as thriller) throughout the cruise to then perform in the theatre or flash mob, crew talent shows, passenger talent shows, karaoke progressive round ending with theatre final, sometimes additional performances (with different content) from guest acts, sometimes additional performances from orchestra, ceremonies (crossing datelines, crossing equators), one off performances by the cast of the main shows.
A perk - on the transatlantic cruises I’ve done - is they tend to be about 70% capacity or less and usually there will be very few children.
We do like the longer cruises as you really get to spend more time talking and meeting the crew.
I saw the price of the cruise you are referencing a few days ago - at those prices I would be on it but my partner has already used his annual holiday allowance for our booked cruises this year. Even suites are a ridiculously low and tempting price for the sailing.