There is room under the bed for suitcases unless they are exceptionally large. Sometimes your room steward can stash them for you and your room is quite large because of no balcony and you could stack them in a corner.
Sun Princess (2 times), Mississippi Queen, Dawn Princess, Coral Princess (2 times), Regal Princess, Grand Princess (2 times), Diamond Princess, Maasdam, QM2 (16 times)
I stayed in this room last year and also an interior inside cabin. They have the same sq. ft. Plenty of space to place large luggage. Many corners and under the bed. Save money and book this room....You will be out the room more then in the room...
We find that putting the empty luggage inside a larger bag (one inside the other) takes up less space. There usually is room to store it (or them) under the bed. We have a very large Hartmann carrier, which when left open and flat, just slides under the bed. Do ask for help from your room stewards!
As well, once the bags were stowed, we found the area of the porthole itself was a great place to stash things ... sorta' like a recessed long shelf, good to lay out sox & shorts & belts, pocket squares, whatever.