We had cabin 8176 which I think is category 2 on Millennium in February. It was a handicapped cabin.
Our balcony was huge - 10 x 20. The lower the floor - the larger the balcony - maybe you should look at our cabin, or the one level below us.
The rooms were larger than ours on Princess but I didn't think they were that practical. The drawers were odd shaped and not practical. The minibar was stocked and we could not get them to remove the contents, etc. . We had a chair in our cabin - some have couches.
Email me if you want additional info.