Since most of your spending will be outside the US, this is key (bolding mine).

It might make sense to get one or two cards, rather than playing the bonus game, and put all of your spending on those cards to really maximise the benefits without having any rewards eaten up by FX fees. You could potentially get another card or two with an FX fee for the bonus right before a US trip and meet any spending requirements during that trip in the US to avoid the FX fees - then cancel after the bonus posts and you are back home in the middle east.