We had M74 on our Xmas cruise last year. Two adults two tall kids 9yr old girl 11yr old boy.
The cabin had one fold down bed..good size, and the steward brought in on cot for the floor. Yes it was a little cramped, yes it got hectic in the mornings (one bathroom) and getting ready for dinner was a chalenge! One nice thing about the layout is that if tou open the Bathroom and closet door tou actually have a nice private are to get changed..small but nice.
Tips... Bring a power strip,only one outlet in thhe room,one in b/r. Invest in one of those over the door shoe organizer. One other tip you might want to invest in the soda cards for the kids $30 each but it will save on the sign and sail acct...lol Our room steward was great don't know if you'll have the same one. There were some great/friendly crew If you have any particular questions I would be happy to answer them if I can.