Okay then.
For July 29, 2023 on the Fantasy a Deluxe Family Oceanview Stateroom with (extended) balcony is $6,618.76 for one adult and one child. For two adults and one child it's $8.476.90.
For July 23, 2023 The Haven Forward-Facing Penthouse with Balcony is $7,886.74 for a party of two. For a party of three, it would be $9,035.81. And this is
including the "2nd guest free" promo. So you can add about $7k to each for the non-sale total.
So in this case, Disney is the cheapest.
As for the rooms themselves, the Haven Forward-Facing Penthouse with Balcony does have separate living & sleeping areas, but by no means is it a massive difference vs. the Deluxe Family Oceanview Stateroom on Disney. For NCL, the room is approx. 451sq ft with a 32sq ft balcony (though
cruisedeckplans.com puts it at 387sq ft and 33sq ft). On Disney, the room is listed at 299sq ft including the balcony, however, when you look at
cruisedeckplans.com the room is listed as 256sq ft, and as this particular one is a 4E balcony, it's at least twice the size of the listed 43sq ft.
Honestly? This took very little time. Never underestimate the motivation and skill of someone who recently finished Grad School.
And why did I go to the trouble of taking maybe 10 minutes to price-compare? Because, and call me crazy, I like having accurate information out there. Comparing NCL's sales of "2nd guest free" or "3rd and 4th guest free" or what have you to Disney's non-sale price is neither fair nor accurate.