It can be a bit dark on the One tree hill side of the road from HOP station - agreed. If you feel a bit unsure, walk on the built up side. You could always get off the train at forest Hill and walk up from the other end of Canonbie Rd (the Honor Oak rd end) a good work out for the calf muscles!

The estate you refer to has always been fairly quiet. I wouldnt be surprised if quite a few have been privately purchased (great views of the cemetary on one side and park on the other!).

At the end of the day nowhere is totally 'safe'. But I was very pleased to be back in Forest Hill a few weeks ago having taken advantage of the Overground, visiting with interest 'the other side' of London.