Suggestions:
-A button in size and ages: Min (all)
-Flags (Later I will explain how to do it)
-More countries on world map (there are 165/206)
With flags, you should add a button to turn the display of the flags on and off. The algorithm to create the flags could be vertical and horizontal stripes with a basic color palette (Red, green, blue, yellow, orange, black, white, and purple). It could be edited in a similar way to when you create a map. However, apart from being able to choose a flag for a country that already exists. When putting a default map like the world map, they should put the original flags.