Dream or Magic?

Planning a cruise for 2017 – Dates aren’t released yet, but based on 2016 schedules, I think our preferred itinerary will allow us to choose between Dream and Magic. I know about differences in amenities, but does the larger number of people on the Dream make shore excursions (esp Castaway Cay) noticeably more crowded? Not sure which option will be best for our family so any advice is appreciated!