I like a lot the sofa image render, very nice
some notes :
- Seems that you used Z pass i guess in Photoshop, there is some bad hard edges in the focused area, better use the Corona DOF ( great results but you should be patient ) or an AE/Nuke plugin...
- I agree with Keymaster about the curtain material, it's like matte plastic, you should play with a high value of the translucency.
- Didn't like the background image , try others a little bit bright but not too much blured...
- Floor bump is too high