Ovation OTS - Ocean View Balcony vs Large Balcony

[Aus ATC]

We are looking to book our first cruise on Ovation OTS and have a question about the standard balcony vs large balcony cabins.  The interior size for the standard balcony cabins is quoted as 198sq ft, while the large balcony cabins are quoted as 177sq ft.  The deck plans seem to suggest the cabins are the same size (understanding the large balcony cabins are on the slant of the humps). 

 

Just wondering if the large balcony cabins are indeed smaller - based on those numbers they seem like the old "deluxe" cabins, whereas the standard balconies are "superior".  We have sailed in both and found the smaller cabins just that bit too small.