For starters, let me say everyone should visit the Panama Canal, via a Cruise Ship. It is one of the most spectacular places on earth. However, be cautious of the WHOLE Itinerary.
Our itinerary looked great, Aruba, Cartagena, Panama, Costa Rica, and Jamaica with 4 days at Sea. When the shipped Docked in Aruba, we were there for 4.5 hours. We didn't have enough time to really enjoy the island. PLUS, the Tour Guide never shut up. He spoke aimlessly about nothing.
Caratgena was nice, but the shore excursion added to much fluff. We didn't need to pay to see local cultural dancers for 10 minutes, break dancers for 10 minutes, and a torture chamber on vacation. I would avoid the Palace of Inquisition. When our tour guide explained how they would tie the ropes to a certain part of the man, then stretch them out, let's just say I didn't need to hear that.
Our Cabin Steward was phenomenal. She made us feel very welcome.