Carpet? Our previous camper had carpet in the bed rooms and living room area and linoleum in the kitchen. Although the carpet was nice, it was a real pain to keep clean. Our new 5er has no carpet except in the slide-out areas. It's so easy to just sweep. We have throw rugs now. Your option, but installing carpet in a caper is not that much different than doing it in a house. It's just stapled directly to the floor instead of tack strips along the edge of the way, especially where there are slide outs.
About the couch? We got a 3 seater recliner from Value City Furniture for our last camper. We removed all the stand alone furniture. The backs were removable and once in the door, I added wheels so we could move it facing directly to the back window and the television:


Current camper came with an electric reclining love seat size couch with the high backs so your head can actually rest.