So many people here hate Byz and will post negatives in even the most reasonable threads. We used to have more cores as Byz, but get this, rather than clean up the AI which is total shit at dealing with rebels, they removed cores from Byz so that it was less likely to pop back up again later due to rebels lol
Whatever, the best time to play Byz was 1.51 one when you could, before game start, scroll the clock back and forth and end up with all your historical cores, and then cheese your way to victory, however, the quickly patched the forward back bug, and soon thereafter made scorched earth almost useless because, again, they didn't feel like making the AI smart enough to determine when going into a scorched earth province was worth it.
There was a time, basically before Common Sense when every patch negatively affected Byz in some way, even if indirectly, nowadays, I think it's about as low as it can go unless they change some of the starting diplomatic relations so it becomes impossible to ally certain countries.