As to the staterooms, the overall layout was very similar. Our bed was by the closet - the layouts actually alternate between that and bed by the window or balcony. The main difference is the size - we usually go with a basic verandah room on DCL, and had a D4 oceanview balcony on Allure, so pretty much comparable categories. There is room for exactly one person to pass between the end of the bed and the wall, so the room is narrower than on DCL. Door to window, there will be a small side table, the bed, another small table, the couch, and the window. That's it, other than the bathroom. The closet opens toward the room, not across from the bathroom. When the couch is opened into a bed, there is about a foot of space between it and the desk - just enough to pass through. The couch opens into a full-size bed, rather than a twin. We had a pull down bunk, but didn't use it. Frankly, I could not imagine having more than three people in this room, unless one was really small. Balcony size for us was comparable.
As to the bathroom, we didn't really miss the split bathroom as much as we thought, and were fine with our little shower 'pod'. We were glad to bring a shoe holder for extra storage. The only outlets were on the desk - I think there were three outlets total. No outlets near the beds, so we were happy to have brought a USB charging hub. There is a clock with an iphone dock, but the connector is one of the old, large ones - if you have a newer phone and need a lightning connector, you'll need to bring a converter.
The lights do not require a card. The AC is the basic colder/warmer dial. Our room seemed warm, so our room steward had maintenance change something in the ceiling to allow colder air to come through. The bathroom had tons of hooks - at least 6. The shower has good pressure and lots of hot water. When you turn out the bathroom light, a very faint light stays on so you can see without turning on the main light.
The most annoying thing to us was the fridge - is it a mini bar, so is stocked with water, soda and snacks that incur a cost if you use them. The fridge itself is about the depth of two cans of soda, so leftovers definitely don't fit.