You can make the lampshade a seperate model, then turn off that model for that light. Of course you might not want to have that model cast any shadow from that light source at all either. (the wires looks a bit odd, ususally real light diffuses close up stuff like that more) You might need to make that material illuminated…
You can just add a light up in the sky somewhere. Lights can take a long time to tweak right, good just to play around with them and see what you can do. (I've spent hours lighting simple things before) You can also use 2 lights for your lamp. One with shadows, one without (both half bright) that'll give the shadows and…