We were on the Thurs-Mon sailing that only stops at Cozumel. True the ship is small, but we never found ourselves bored. The pool deck was maybe a little tight, but we were able to sit along the edge of the pool to cool off when we wanted to. We ate in the main dining room most nights (check your table and seating when you board-ours were both wrong, but they easily fixed it). We found the food to be above average and enjoyed the experience there. The Windjammer was pretty cramped with long food lines. If you enter on the starboard side, you will miss some offerings on the port side unless you go ALL the way around. We did the sea day brunch one day, but found the offerings a bit odd (fried fish and beef stroganoff just don't resonate "brunch" for us). We love trivia and participated in several on board. Isaac on the cruise director's staff is absolutely hysterical-don't miss his Musical trivial! The Love and Marriage Show, hosted by Cruise Director Elvis was also very funny. We didn't make it to any evening production shows.
Our cabin was 7180 and like others have said, very small. We were able to unpack everything in the available closet/drawer space, though. There is actually a decent amount of storage space in the (tiny!) bathroom. We had a very sweet room attendant who made me a bookmark when she saw my stack of books on the nightstand, which I found to be a very kind gesture.
In Cozumel we did a private jeep tour (not through RCI) and enjoyed it very much.