Preventing Rebellion

[Quietus]

Don't move your Sultan around, just keep him in one place. In your case, the best would be Constantinople. Then, try to control the sea provinces. You MUST have every single space.

Also, don't forget those religious agents, and spies (one of each per province). Use a lot of emissaries as well as a scout.

[Uesugi Kenshin]

Or you could be historical and keep him in the true capital. Ankara, amazing that they dragged that huge cannon to Constantinople from there.

I almost always get 1-2 chan rebellions where huge swaths of land rebel, then my navy ships in elite troops from training centers and the front and I crush them with my iron boot, they don't rebel for a while after being mobbed by 5-10k of the best troops to ever walk the Earth. Remember to keep a strong navy, then you can easily respond to rebellions if you have a strong military.