Well, I finally took care of the Polish early in the game last night. The pope ignored me cause I was swift enough (if you invade, he gives you a warning to stop within 2 years and return all the lands of the Catholic faction, else excommunication... but if you can eliminate the faction in under 2 years, you are golden). I had to deal with quite a bit of the Pole's friends like the norvogods and Byzzies. Snuck up from the south and attacked the Byzzies king. I manually fought the battle and cornered and killed the byzantine emperor. He had no heirs, so the rest of the empire fell into rebel factions. I cleaned up all but one area where his two major armies sat.
I tried many-a-times to get a ceasefire from the norvogods, because I know I have maybe 30 or so years before the Mongols invade, and I want him to have to deal with them first. After trying for a couple years, one of my daughters comes of age, so I offer her to be wed to a norvogod prince, which solidifies my peace with his country (it has one small disadvantage of if me and all my heirs die, the price has claims to my lands). I also offer my next daughter to France to keep them far off my back, yet the french king refuses (surprisingly, but I already have a strong alliance with them). I have two sons, both incredible generals now, and I convince the norvogod's king to give me one of his princesses for my older prince. This is a good thing, because norvogod has very few heirs, so if the mongol's invade and take them out, I'll nab the rest of russia by default.
While this is happening Sicily and aragon (between spain and france) both repop up from a secret heir with big armies. Spain is now tied up with the Aragon army, the French army, and the Turks. He actually sends me a princess for my other son to wed for help. I tell him to screw off, and contemplate assassinating the princess as a way to get through to him that I'm pissed off at him (but I'm far too nice).
I start examining my princes to see who I want to become king (my Doge (king) is getting old). The older one is a great general, but he's having secret adulteries that, if the Pope finds out about, would get me in hot water. The other is a Hedonist, which is bad, but not horrible. I have another son who will come of age soon. Better work on getting some high level assassins in case he's the best one to get rid of his older brothers...
While I'm contemplating this, the Pope thinks its time to reclaim control of Rome. The King of Rome is the uncle of the current ruler. I wanted him to be king, but couldn't assassinate his older brother fast enough before my original king died. He has all the best virtues and no vices (he is kind, charitable, a great general, and loved by both his people and his men). I gave him control Rome as it is now my largest and most upgraded cities. I am outnumbered nearly 3-to-1 from the pope's army, but my army is balanced and very veteran, whereas the pope has mostly peasants and archers. I do the battle manually and it is a route. I make sure to let the pope leave unharmed (I coulda killed or captured him, but its best that he stay controlled in one area without an army). So now the king of Rome is even greater of a man. I should start assassinating every noble born until I get to him as king (his two other (younger) brothers are great generals, but horrible men. One is a stupid drunkard, the other is a known pervert).
And then the Byzzies make a comeback with their secret heir. They take the one area I failed to grab, take out both armies with a superior army, and cause rebellions on crete and a small island, and Constantinople.
Now I have another delimma. Poland, next to the new Byzantine empire, can't withstand the new Byzantine army, so that tells me to make an alliance, but I really want to control constantinople, which I could easily overcome if I send in a crusade, but that means war with the byzzies.
During all this time, I am pumping out an enormous Navy. I have sea control over the entire mediteranean and the black sea except for two spanish ships (they'll both be gone next turn). I am working on controlling the northern coast of Europe in the coming years. Control of the sea means control over trading. I am easily making more money than I can spend. I may just have to create another enormous mercenary army to eliminate the byzzies again... What I really need is to simply assassinate the new Byzantine and Sicilian King to put them back into minor rebel factions again...
For those interested, hopefully I have given you a taste of how intricately complex the game is, yet how fun and complex and challenging it is to play.
I'll try to take a few screencaps so you can see what all I'm talking about...