Where are you going now? I'd suggest finishing off the Sicilians and then preparing to fight the Milanese, French and Turks... and the Holy Roman Empire and Hungary for good measure, because you can bet those bastards will stab you in the back once you get anywhere near finishing off all your rivals.
Picky picky picky.
The Byzantines still have one city left, and I want to finish them off permanently. To remove one more navy from the Meditteranean if nothing else. After that....hard to say. The Turks are tempting, as taking them on will let me keep the Pope on my good side. On the other hand, Milan will attack me sooner or later, so hitting them first would be wise.
Sicily is tempting to, though. I'd have good control of the sea, so....
I'm actually planning on letting the Holy Roman Empire rest for the moment. They haven't made any overt moves against me, and they'll have plenty of enemies in the Dutch, French and Hungarians. And the Hungarians have the Romans and the Russians to deal with. I might take them on eventually, but they can wait. And France is still a ways away.
And the Turks have one more advantage, I'd be alot closer to Jerusalem, which I'll need to take eventually.
So many choices.
Missed all this getting updated. Get a guard on Venice and I would have crushed the Milanese first had I been around to vote. I strongly recommend you redirect all those armies you're currently using to put paid to the Sicilians and rush them up north to annihilate the Milanese. Just keep a fleet around the Sicilians and make sure they can't fire off an army; they've got the Spaniards to worry about anyway.
If possible, see if you can't maneuver the Sicilians into getting excommunicated; and remember, you can always kill the pope if he doesn't cooperate! Rome really isn't that hard a target...