Hey,
So I got a domain in the format of
country.domain.tld

The site is targeting English speaking countries and will be active in UK, US and Australia

so a couple of quick questions would be
A) What link structure would you recommend for these sites
B) Even though the pages will be different in the different countries would you recommend to use HREF lang meta to make sure search engines now what country each page is targeting
C) Any other tips for a multi country domain would be welcome