We really think that the Wish's adult-only pool area is sad and pathetic. But we've sailed on her twice (a four-day and a three-day), and we're sailing on her in November this year (3-day). If you're getting off at
Castaway Cay, you probably won't be spending much time in the pool. And if you're not getting off at Castaway Cay, you'll have the pool largely to yourself (not to mention being able to ride the AquaMouse multiple times in a row without getting off).
We spent a lot of time in the Rose (especially during sailaway- amazing views - and when at Castaway Cay), the Bayou (coffee and beignets in the morning when hardly anyone is up and about), movies, shows, trivia, snacks at Keg & Compass, sitting on our verandah, lunch, ice cream on pool deck. We rarely found much time to spend in the adult-only pool area. We did manage coffee a couple of times in the Cove Cafe.
Now if they have the exact same configuration for the Treasure - for a 7-day cruise, I might mind the small adult-pool area more than on a three or four day where there are so many other things to do that we didn't have a lot of time to spare to go to the pool. But then there are usually more things to do on a 7-day. We'll have to wait and see.
So, while it's not my favourite ship, and the design has some drawbacks, it's still as good a ship for a couple as the others IMO.