My first cruise was on Fantasy - I had an Ocean View. My second cruise was on Fantasy - we had the Ocean Suite. No contest - if it's within your budget, go for the OS for the balcony alone. Priority embarkation and disemarkation were also nice. We sailed out of Mobile.
I've not been on the other 2 ships you mention. Here are the dimensions: the OV was 185 sq. ft. The OS was 220 sq. ft. with a 30 sq. ft. balcony. It was the ideal size for 2 adults.
IMO, considering that over 2,000 people are being fed, the food was quite good and sometimes really good.
Hope that helps!