Can't specifically address Hawaii, but they can't bring on extra scenery, etc as they have limited storage space. Also, the cast can only rehearse and do so much.
On 14 night TAs and Panama Canal cruise, the theater staff did some relatively more simple shows--Once Upon a Song, a tribute to Walt Disney, etc. They also brought on outside performers. Some cruised with us part of the way (or all the way) and others came on for only one night. You will not have any repeats, and something will be happening in the theater each night....and only one night will be a movie. They'll keep you busy.
Once Upon a Song used the stairs from Twice Charmed and featured 5 or 6 of the performers with a couple of costumes each and very few props. Much more simple than a Broadway style show, but very enjoyable. In Barcelona, we had a flamenco team--amazing. In Curacao, Susan Egan and her accompanist came on for just that evening--again, amazing. We even skipped dinner to see her show a second time. (she played Belle on Broadway and did the voice of Meg). On another long cruise we had a concert by Jodi Benson (voice of Barbie in Toy Story, etc).