In my games everyone just allies with each other and none of them do any fighting. I just chug over faction after faction.

Enough of my problems, take Geogia from the French and do not move east of Constantinople. That secures the east. Now take out Germany and Poland to shorten your borders. Now take a few turns to consolidate and retrain your frontline troops.

Then basically role east, take out Italy and Denmark as you go. It shouldn't be that hard, provided you advance at a steady pace, keep up the presure and don't over stretch. Regarding navies remember, "Hold the seas we must, live if we can." Naval power is everything.

Once the Pope is gone just kill everything else.