I don't know whether you really need more lighting for this model especially since you're using Cycles as a render engine.  Are you looking for a more realistic environment for your characters?

I downloaded and looked at this model after importing the FBX file into Poser 12.  I'm impressed but not too crazy about integrating all the bedroom objects into one mesh.  Yet, for Cycles rendering, not bad.  If you angle your camera toward the ceiling you will notice recessed lamps modeled in.   You can change the shaders for those to cast Blackbody emission lighting into the room.  Fortunately, you change the material for one and they all will be set.  I took the liberty of changing all the visible components in the attached render to Cycles materials, overhead lamps were converted to mesh lighting and I placed Blackbody point lights at the bedroom lamps.  I think the point light on the left lamp might have gotten embedded in the mesh so the brightness is muted.  I really think this is how it should look.  Just my opinion.