What join were you given from the West?
I agree, it is hard to find from the West, but there's never a lot going on at night. You could request an overhead join at 2,400ft QNH then descend on the deadside for standard circuit join.
From the West, I normally aim for the VOR, then refer to the row of street lamps on Main Road, just outside the Tower, plus the apron flood lamps. The red beacon on the VOR is also a clue. New Addington is also helpful, but all of these are poo if you are given a straight in or left base for 03 from the West in the dark.