I would go in April because the breeze off the ocean can be cooler in March making it less fun on the deck. I would get a room midship if you do not like the rocking, which is usually minimal anyways. And lastly, I prefer to have a room 2 floors down from the main pool deck. Its easier and quicker to walk to your room and back if you are a sun worshipper and its far enough away from the main deck noise which can be heard on your balcony or through your room celing.
Being from New England we like to get away from the winter. By March cabin fever has seriously set in. Either would be fine, book it now it will fillup fast. March is Spring Break for the colleges so families with college-aged kids have already booked, same goes for April when the primary schools are out on their Spring Break.
Stay away from upper decks, mid-decks mid-ships are the most stable. We like Caribe, Baja or Dolphin
Just back from the Caribbean Princess. We were midship on the Riviera deck. DO NOT GET A CABIN ON THIS DECK!! We were directly under the buffet/pool deck and it was impossible to sleep/nap it was so loud! I would go to deck 5 or 6. We were on deck 14.
CCL Inspiration 09
RCCL Explorer of the Seas Eastern 09
CCL Miracle Southern '08
RCCL Enchantment of the Seas Western '07
PCL Caribbean Princess Eastern '05
RCCL Explorer of the Seas Western '05
RCCL Explorer of the Seas Eastern '04
CCL Destiny Southern '01
CCL Sensation Eastern '94
CCL Ecstacy Western '92
CCL Jubilee Eastern '90