Thanks now I think i have just about enough info. to start work on a TL of sorts.
But one more question, this Arab exodus would it make it more plausible for the Mongols to convert to Christianity, Hulagu was rather closer to Christianity than Islam so maybe Egypt becomes Nestorian or would that be ASB?
I think Hulegu would hedge his bets if he meant to keep Egypt at all, until it because clear who was more useful.
Muslims provided a LOT of the bureaucracy for the Mongols, whereas the Nestorians were mostly from traditional Mongol warrior clans, who are going to lose relevance in a generation or three.
Who could replace the Muslims? Copts. Greeks. Armenians. Not the Franks though, they had a tough enough time finding administrators of their own. But there has to be strong advantages to converting.
Having Berke die early and the Jochi ulus stay pagan/christian could actually help too, but nothing's guaranteed. In 1260, Islam is glitzy, rich and well-educated, something Christian Eurasia has few answers to.