The data visualization of this article although it presents some interesting data, presents it in a very disorderly and dispersed way. I think that the colors they use are not big differentials at the moment and make a reading of the figures.
For me always a data viz, it must be very explanatory and clear. The collected data would have been presented not only by means of maps, it would also have made use of data bars, with strong colors in the information that I intend to highlight.
I attach the data viz link
https://www.arcadiadata.com/blog/brexit-insights-from-data-visualization/