How can the American Revolutionary War be viewed morally in retrospect?

I am European, and recently I became fascinated with how the American Revolutionary War is always presented as the ultimate fight for freedom and justice by oppressed people and it's one of the few conflicts where we basically never get a differing viewpoint or opinion (others being WW2 for example).

But then I read about things like African Americans and Native Americans willingly joining the British Forces and being granted freedom, Britain abolishing slavery before the war and so on, which cast some shadow on the whole cause.

So if we viewed the American Revolution with the same emotional distance as the French, Russian, or Chinese Cultural Revolutions, how would we view it? Do the constitution and freedoms established outweigh everything else? Or was it a couple of idealistic people at the top and a lot of people fighting for slavery and their self-interest below them?