Ah, I realised after more experimentation that by moving the lamp closer to the shade than it would be in real life, gives me further control over the shape of the glow behind the lamp:

I still don’t understand how you get the slight hue shift though- your lamps start out white and fade through a yellow through to a warm orange which looks great and really makes that bedroom homely. How can I reproduce this? It seems Cycles is only shifting the value not the hue for me in the current scene (on Blender 2.79).