This is our fourth transatlantic and we really enjoy the relaxed sea days. There are still plenty of activities to choose from. Also, it is easier to adjust to the time changes since it is more gradual.
The shore excursions to Berlin and Paris were all day and long but extremely worth it.
In Paris we took the riverboat lunch cruise and it was outstanding (our second time for this tour).
Very convenient for everything and the elevator was rarely a problem.