As much as I despise the bland sameness of most suburban life and prefer the hustle-bustle of cities and diverse neighborhoods, I would caution against the Langstrasse in Zurich.
A good friend of ours was just released after a week in the hospital. He was walking down the Langstrasse in the evening, when a woman came up and started yelling at him and smacking on him. He ignored her, kept walking - only to have her boyfriend or pimp or whomever he was come running and beat him up. His jaw was broken, among other things.
My husband has a radio show a couple of times a month at Radio LoRa, which is in an alleyway around the Langstrasse, but in an OK block (right near the police station), but I am still rather hesitant if I go along and I don't drive - standing and waiting for the bus at 10 or 11 at night is a bit unsettling there!