When I went to schools (40 years ago) history was all about the saxons, romans and vikings. Plus a bit about WWI and the Russian revolution. I don't remember doing anything much about the British Empire. But it was always tacitly assumed that the British Empire was "a good thing".

I think most educated British people now know there is quite a lot that was "problematic" about the empire. Interestingly there is a very good new British podcast called "Empire" which talks in a lot of detail about what the British did in India and it is not comfortable listening.

I would say the British Empire wasn't as cruel as the Spanish, Portugese or Belgian empires. But that is a very low bar.

Unless you were a baron or a lord, I doubt many British people got any benefit. Britain and most of its old colonies are pretty multi-cultural now (more so than any other countries colonies) I think that and standard english are probably the only real benefits we can see today.

I expect a lot of the resources from the colonies were used to finance the Royal Navy.