One of my most standard criticisms. It's like people don't spend any time at all researching dataviz color scales. A quick Google search will bring you to Viri

One of my most standard criticisms. It's like people don't spend any time at all researching dataviz color scales. A quick Google search will bring you to Viridis. Use that or one of the many similar versions in other hues. Also: the title of the chart is "Least Religious Countries", but the chart is colored so that the top of the scale is "100% Importance of Religion in Daily Life," i.e. the most religious.