We always sale Royal Caribbean. You cannot beat the level of service that you receive. We have learned that it is not about the port of calls that you go to. It's truly about the ship and the staff that make a cruise worth spending the money, and Royal Caribbean always goes above and beyond.
Empress of the Seas is a smaller boat and lacks the features of some of the newer bigger boats. If you are wanting to just get away, relax and eat than you will enjoy the Empress. If you like being active with a nice weight room, sports activities and new features you will want to book on a different boat. The Empress still had great entertainers. Ronn Lucas was absolutely hilarious. The cruise director and his staff did a wonderful job hosting all events.
The dinning options are still great. The food with Royal Caribbean is always excellent.
If you are able to, I would spring for a balcony room. The interior rooms are small and do not provide a lot of room for two people to move around. Either way though, you're on a cruise and will enjoy it.
We rented bikes and rode around the island. Key West does not have nice beaches or much else to do. I would not book a cruise based off this port.
We rented a taxi with Vincent Dudley and toured the Island. Previously we visited Stingray City and loved it. This is a must while in Grand Caymen.
What is not to love about Miami. We stayed the night before setting sail.