@blatham,
What I found interesting was the effect on me.
The rich people are victims, and not really terrible people.
I know they're vacuuous and shallow, but not wicked.
However, when they died I didn't give a ****.
I wasn't exactly rooting for the protagonist, but I was very forgiving despite him being more than a little creepy.
I always Olivier a bit hammy, but I don't know if he should have adopted an accent.
The Moors were primarily North African, and also briefly of Iberia. They would have been familiar with the Mediterranean and probably had local accents.
Venice was very cosmopolitan at the time which was why Shakespeare used it so much.
There is a really good version Othello by the RSC with a black Othello and Iago. I saw it at the cinema live streamed from the theatre.
It now looks like it's on general release.
It works really well, Iago has enough to be pissed off with Othello as it is, and Othello remains The Moor while Iago is just a Moor.