When you go on the newer ships like the Spirit Class ones, Spirit,Legend,& Pride and probably even newer ship that are just out or coming out, you won't want to go on the smaller older one again. (unless you like smaller ships, it is a matter of taste).
With the Imagination (which I have been on 5 times) the cabins are 175 sq feet. Spirit, & Legend (which I have been on too) are 185 sq feet. A bit larger, plus there is a refrigerator in each room.....If you prefer outside cabins Spirit and Legend has 80% more outside cabins.
I found the service excellent on the newer ship, and the food much better. The only reason I went back on the Imagination last Nov. is that I got such a great cheap price for 5nighter I could not refuse......I love the big ships.....
Right now the rates are pretty inexpensive so if you can catch a great deal book it now and if the rates even go down further you can get a reduction in your price. I always do.
Which ever ship you decide to do enjoy your cruise.....
Marilyn (cruzmama59)