What shape you got (stick it in your signature, make life easier in future) I found having my lights properly aligned made a big difference, as did fitting new headlight units, 1 got smashed so I had to change it, the difference was massive so I looked for another cheap on ebay and changed that too.
It can be worth cleaning them out use window cleaner and a bit of rag on a stick, then rinse with really hot water from the tap before drying them in the airing cupboard.