When guests first click on your listing, it shows your first 5 photos. When I had it by room, it showed 2 photos of the living room, two photos of the kitchen/dining area and one of my coffee bar. It showed nothing of the bedroom, the big screen TV or anything else.
So I rearranged my photos so that the first 5 photos show what I feel are 5 important things about my home. The living room, the kitchen, the bed, the big screen TV and a dedicated parking place for guests. Guests get a sample of what I'm offering and when they click on show all photos, the rest are in order by room. It's a basic marketing strategy.