I think you should've model bigger house to cram all those models you have ;] Space looks very crowded and uncomfortable.
you're right it was also my thought , but I received " orders " to place all the objects that are in the scene:)
Your couch models/materials look like really strange to me. It seems as if they have an intense Ambient occlusion going on, very distracting when compared to everything else in the scene.
yes the yellow couch material has some problems , maybe AO as you say , I have to check , unfortunately for lack of time I could not correct it .
Thanks for your help!