My main site is all English and is visited by these top 20+ countries
 

Don't limit your thinking to where you're located unless you want to be a specialist for your geographical/national area. What's more how important is your content and it's relevance to the size of the audience you want to attract. If you want a vast audience it's as simple as building a site to address their needs.
If you have the right niche your audience can easily be worldwide.

My main site is all English and is visited by these top 20+ countries in the following order:

United States
United Kingdom
Canada
Australia
Netherlands
France
Poland
Germany
Italy
Belgium
Turkey
Brazil
Mexico
Switzerland
Japan
Finland
Czech Republic
India
Spain
Sweden
Norway
New Zealand
Greece

and on and on...

Note how high up the Netherlands, France and Poland ranks?

The site is all English so that has always surprised me as I figured New Zealand and India would be much higher up the list!