I've got to say, this is one of the funnest games I've ever played, easily. I've been in the middle of a Byzantine game recently (starting with the ascension of Alexios Komnenos)... I'm in the year 1261, shortly after the death of my greatest character ever, Adrianos I Komnenos ("the wise" - he got that nickname really early into his reign), who was a genius with mid-twenties stewardship skill and in the mid-to-high teens at everything else, conquered the Holy Land, Antioch, Dalmatia, and most of the remainder of Italy (I had conquered the southern Italy and Sicily about fifty years before Adrianos came to power), including Rome, and reigned for 60 years, finishing with a score of over 34,000. I now control his son, Nikephoros V, who is also a genius with very high martial, learning, and stewardship scores - although, he is also in his mid-forties, and is maimed from battle against the Turks, and has a rather mediocre heir, especially compared to Nikephoros, Adrianos, and the Emperor before that, Manuel I. The goal for the rest of the game? Try and reunite what was the Roman Empire at its height - and I think I've got a pretty good shot, especially how France, Iberia, and Great Britain have been pretty chaotic over the course of the game (What happened to France is actually pretty crazy - most of it was conquered by the Almoravids during the early 1100s,, but they united their crown with Castile and Leon, so while Paris was conquered a long time ago, the Kings of France have been fighting to regain their territory from their seat in Barcelona! Recently, they've started to recover some of their territories, but the Muslims still control most of Aquitaine, and the Holy Roman Empire, Brittany, and England have large chunks of the north and east.). Anyways, I've been pretty lucky so far, so hopefully that continues, and I avoid getting idiot heirs or being overthrown or something, so that I can succeed in bringing Rome back to its glory days!
My first game was as Philippe I Capet in 1066 - I eventually gave up on that after I got stuck in a huge civil war with an infant King a hundred years down the road or so, after I inherited some of the Spanish Kingdoms. Shortly after, I retried that same scenario, and so far, that's been the only game that I've played all the way through to 1453. I ended up ruling (nearly) literally all of Western Europe, ruling pretty much all of modern France, most all of Iberia (there was a little HRE-controlled outpost in the south), and all the British Empires, with an end dynastic score of around 150,000. Fun game - I especially liked playing as the alternate Philippe Capet, who had a score just over 20,000, and set the tone by ruling for nearly seventy years, and conquering Andalusia and the Holy Land in successive Crusades. Most of that Capetian dynasty tended to be strong diplomats, whereas in my Byzantine game I've preferred to make stewards.
I've had a few other games starting from much lower positions (one in which I rose to become King of France, and a couple others where I've done some exciting things), but they're not as cool stories, and there's not much point in posting all of what I remember from my games on here.
As for the new DLC... it's a fun idea, I guess, but I'm not going to get it. Too bizarre and ASB - not that CKII can't already get a little ASB (I recall a game where I suddenly found that Scotland had become a Sultanate, albeit still Catholic, under Abu I), but that's getting a bit carried away to create a challenging menace in the west for my tastes.
Anyways, awesome game.