In my (limited) experience east London always had an edge to it but I thought the places that felt really dangerous were south of the river. Peckham used to feel awful but the Damilola Taylor murder in the 2000s really was an eye opener in terms of what human beings would do to each other In the city. Now you have to give one months notice to get a restaurant table there.
Part of the deal I made with my wife for moving to London was that we would rent a house with a garden. Unfortunately that always seemed to require living in places where drug murders kept happening . Swings and roundabouts.
Brick Lane is unhangingoutable these days (crowds of millennials, hipsters, tourists and City people). I'm based more to the east and now living even further in the most soul-less district of London, Isle of Dogs (no offence to dogs). Today my friend saw forensics investigating someone's body "sitting" on a bench!