Filled map region delimiter countour line

[Anonymous]

Hello everyone.

I have a simple, short question.

In this map, it is difficult to tell different regions apart when they are adjacent and have a similar color, as the ones pointed with arrows:

Doesn't look to me like the visual lets me mark the countour delimiting my regions, or anything in that regard. 

¿Does anyone know any workaround this problem?

Thanks in advance,

Alberto.

[themistoklis]

@Anonymous 

With filled map you cannot changed the width of the boundaries.

Try another visual (e.g. MapBox or ArcGIS)