The larger room would be way more comfortable for all 3 of you.
we did a cruise in the Bliss in rear facing haven, and found 2 things that would apply. First is the Haven dining room is not stuffy, but we found it quieter and less hurried than the main dining room (we tried the MDR one night). The second thing is I am lactose intolerant. They were so attentive. I don’t know how many gluten free choices they may offer, but I do know that I mentioned lactose intolerant before the cruise and so they were ready for me, actually in every restaurant to let me know what I shouldn’t eat. Still be a good idea to bring you GF muffins & snacks for just in case.