Congratulations! ooh so much to choose from. I would go for a mini-suite with balcony. That should be fine for the 4 of you. What are your interests? It would be easier to help you pick if we knew what you and your family like to do.
Eastern= white silky sandy beaches with turquoise waters, snorkeling, water sports - great shopping. More at sea days
Southern = port intestive cruise- lots of variety to choose from ( one of my favorite cruises)