I'm currently helping out backstage at a production of Othello, and no work of Shakespeare save maybe The Taming of the Shrew annoys me more than this play!
I get that time is limited, but Othello goes from "I love Desdemona!" to "Desdemona is cheating on me! I'll kill her!" in a single scene! On nothing more than hearsay given to him by Iago. I know Iago has never given indication to anyone that he's a liar until he gets caught, but Othello is still far too easily swayed.
Also, Iago is very lucky to get away with his plotting as much as he does, considering if most of the main characters had just talked to each other, he'd have been majorly busted ("Why would Iago say I'm sneaking around meeting your wife when he's the one who told me to talk to her?" etc)