Pack lightly - overnight laundry is $30 for a cloth-bagful that holds 4-5 days for a couple.
HAL does not have Princess's tracking system. You have to tell a waiter where you are and ask your travel companions for their location.
Strategically, it is often worth purchasing the lowest level of cabin within a class (A, B, V, ...) then getting Club Orange for $25/day and upgrading for free to the exact cabin you want (within that class.)