First, things can always change!!!
I love the REGAL. I love the large Piazza, International Cafe there for food sweets and snacks, That is where the coffee bar is for your good coffee beverages with your package.
Alfredos is also something you should plan for.
I love the Sanctuary, but if you can not board early, spots canl all be filled.
If you are looking for that kind of thing, pool, etc, sailing from FLL, then you can also head to the Retreat pool early and get a nice spot. (I have seen them eventually remove towels/etc left for too long to free up loungers)
Others who were recently onboard can fill you in with more info about. the shows.
I am thinking, guessing, that the two main shows are Bravo and Rock Opera.
Princess shows can be very good. Do get to the Theater early... the shows can be popular and fill up the Theater on some Princess cruises.
Have you sailed Princess before? I believe that they will have the earlier priority boarding for Platinum/Elite/and Suite guests.
If you are not in the US or Canada, then you might not receive your Medallion before sailing. I am in the U.S. so I am not familiar with any of the process and differences. Sorry!!!