Quality of life varies significantly based on where you are in the US. There are definitely smaller cities that offer high standards of living–if that's your speed.
You could start by looking at places that people from the big cities visit for summer vacation. The town I live in has a full winter season, and in the summer turns into a beach town with a lot of regional tourists who boost businesses up with money. Very low crime and thriving local culture. Common to see people not lock their bikes while downtown.
