If you don't care about food, thread count, coffee, or decor you probably won't be too interested in what I have to say... However, if you do -listen up: I learned a few "tips" on this cruise that may be helpful....
#1 Don't pick assigned eating times! Wow, I learned this lesson the hard way... I hate to sound like a snob BUT: A) you will most likely have to share a table B) which sounds "cute" until you realize that C) you have been seated with the most ill-mannered family onboard and... D) you're stuck eating with them for 7 nights! Instead choose open-time seating, this way if you want a private table you can have one (you may have to wait). If you're feeling social and want to share, you can- but you're not committed.
#2 Be prepared for the "singing and dancing waiter routine." To me, it's beyond silly but Carnival is the "Fun Ship" so you might want to have a few stiff drinks to prepare yourself. The first night I about fell out of my chair... No worries though, you'll get used to it by the end of the cruise.