1. Egypt, like Sicily, was a, no, the major supplier of grain in the Mediterranean, but how would a Roman reconquest be seen by others? Venice, Jerusalem, Nur-ad Din, Saladin and the Fatimids would clearly not be happy. In Souther Italy and Sicily there were still Greeks and Christians who followed the Greek rite. In Egypt, there are Miaphysite Christians - the Copts, and Armenian and Nubian mercenaries used in the Fatimid army - and the Sunni and Shiite muslims. Were the majority of Muslims in Egypt at the time Shiite, or was it confined to the upper classes like Judaism was to the Khazars?
2. With a surviving Kingdom of Jerusalem, how much territory in Syria and the Levant would the Romans have to control to exert a greater degree of control? As far as Edessa, Aleppo or even Damascus?
3. I might consider having a more powerful Khwarezmian Empire. If there is a Third crusade, would it be more interesting to have them, a Zengid sultanate (not necessarily under Nur-ad Din's son) or even a revitalised Abbasid Caliphate as the 'antagonist'?
4. Most importantly, even if Manuel or his successors decide to reform the Roman government and military, should I make these conquests last?