There are many negative and tragic effects of England's several-century-long colonial drive. Below I want to focus on one impressive aspect of Colonial Britain.
When I think of management, and examples of the highest possible level of management, the case of the Commonwealth comes to mind. Here is very small (in terms of both area and population) country running the world's largest organization. The kinds of problems England encountered when managing its colonies were unprecedented and massive. How do you manage an entire people remotely; what incentives do you use to discourage the people in the colonies from rebelling?
England was successful as a colonial power because it understood man's universal driving forces – money and power. They built an impressive trade system which likely boosted the colonies economically. I'm not a historian, but it seems to me that England had a near-monopoly on international trade. England leveraged the political systems of their colonies, rather than changed it – the highest positions were British, but below that all was open to the natives; this, combined with provided a kind of power continuum – given enough levels of hierarchy, there was always a more powerful position to aspire to, and with the overwhelming majority of the pyramid belonging to the natives, nobody wondered who actually runs the country.
England during the imperial period is an excellent example of that fact that it's not size, or population, that matters, but leverage. With its unbeatable navy, and a relatively efficient (and definitely ahead of its time) organization England had control over vast lands and, thus, natural resources.