When I play Rimworld or The Sims I try and visualize room/house size to try and get them as close to what I think is big enough without it looking like the hallway is a bedroom. I do this by looking at how much space an object in game uses to real life in this case the double bed, which is 2x2, to me this would be a queen or king size bed in real life, 1 square would be a hallway.
I did a paint comparison of my room and what it might look like in Rimworld. I also used 2 squares as the height of a human which would be the length of the queen size bed.
My point throughout this discussion is that 6x5 for a room in Rimworld is to much to keep your pawns happy, at least to me it is. The room I have linked the picture to is in squares, the squares are there to represent the size of real life objects to Rimworld. The yellow outline is my bed, red is the door and closet and the black/orange is my stand/tv.
To me, my room is quite large, big enough to have an extra queen bed if I wanted, however, its only a 3x4 room, yet its got enough room for everything I need, but the pawns in Rimworld are not satisfied with a room this size and want something more to a living room.
I remember reading about a mod that made it so pawns would be happy with a room of 3x3, however, I cannot seem to be able to find it, or if the mod author even updated it.
My request for anyone reading this post would be, if they have time or are willing, to create a mod that lowers the need for such a massive sized room and allow pawns to be happy with a 3x4 or 3x3 room size.
Link to the bedroom I think is ideal for a happy Rimworld pawn.
http://postimg.org/image/ensajdbtt/