Actually I think that the upcoming plague hinders the Ottomans more than anything else. Often their cities shrink to size 1-2 during the plague, since they lack health resources early on. The plague is also really harsh for the AI, as it doesn't understand to group its soldiers outside cities to garantee their survival, which is at best annoying micromanagement for the player too. Perhaps, SoI's plagues should take a lesson from DoC, where plague doesn't kill units, as it realistically shouldn't.