We did the Eastern Caribbean tour on Symphony. It was a good cruise, the ship did not feel that crowded, some lines but they typically moved fast.
Service was mediocre, crew was not very pleasant and bar service was pretty slow.
Food was also mediocre, but not bad and not great (except for Lobster night, Lobster night was great!).
About what I expected from the cabin, was tight with 4 (including 2 teenage boys 13/15). But we managed nicely and didn't feel cramped as long as we kept the cabin organized.
Brought a USB charging station so had plenty of charging power.
Big balcony (about 10 feet deep and as wide as the cabin).