You can adjust your dining times based on port times.

For example, if you chose the early dining, but the ship stays in port late, then you either skip eating in the dining room or have to hurry back to the ship and get ready for dinner.

We were able to make reservations for each night (pre-cruise) so we never had to wait for a table. We also tried just showing up to see how long of a wait it would be and never waited more than "Let me see what I have. Would you like the same servers?"