yeah, attacking the Byz is about the only way to help them get their much needed breathing room. Esp. if they're able to penetrate the Balkans; after that they can pretty much steamroll their way through Eastern Europe or Russia. So attack the Byz and conquer some provinces, leave the provinces you want the Turks to have empty and then declare war on them and get Armenia and then try to get a truce out of them whenever you feel like they'll be able to survive. Knock two birds with one stone.

Only problem is that you'll probably their first target unless Crusades star popping up and they take advantage of the Egyptians situation or they focus more on Europe.

Hope that helps!