Here’s some interesting data on cost of living and quality of life by a variety of measures for cities around the world.
You can search just on cost of living, best cities if you’re a single guy (or girl), cheapest, safest (for women), and where you can make the most on Airbnb.
I like their list of best cities to work from home which they call their digital nomad list based on “internet speed, cost of living, weather and fun.” The neat thing is you can filter by your own criteria like beach or snow, cold or hot, and how friendly a city is to same sex couples.