Homicide in US cities is an inner city issue. It's not mainstream. There's bad areas - stay out of them.

It depends if pick pocketing is ubiquitous or prevalent only in specific places.

It's not just an inner city issue. Rural areas in the U.S. are bad too! Parts of the rural south and rural midwest have homicide rates that are completely off the charts for a first-world country (Holmes County, MS; Scioto County, OH; McDowell County, WV).

The homicides in the US are not random, they are targeted. There is no need to avoid “bad areas” unless you are attempting to start a new gang or sell drugs there.