If you tend to get cold, you might consider bringing one pair of pants. I'm always cold in the show lounges and usually go back to change into pants.
We are also the type that perfer to stay in shorts most of the time and prefer the buffet to the dining room.
Check to see if your ship has a deli. The Glory did and the sandwiches were great! They also had a pizza, grill, fish/chips place, oriental food, international (changed nightly if I remember correctly) in addition to the regular buffet.