Lets do some analysis on that:Kind of disappointed that in all these pics, Byzantine Empire is still in tact.
First image, 1310, Byzantium has splintered quite a bit.
Second, 1121, Byzantium is dealing with a civil war it seems.
Third, 1177, can't see all of it, but looks like it is in a civil war.
Fourth, 1279, lost most of its Balkan holdings. Civil war. Lost some of its eastern holdings.
Fifth, can't tell the year but the Golden Horde is there, so probably 1250ish. Huge Byzantium.
Sixth, 1101. Player-controlled Byzantium
Seventh, 1179. Byzantium not visible.
Eight, 1121. Intact Byzantium.
Ninth, 1140. Player-controlled Byzantium
Tenth, 1453. Byzantium destroyed by player.
Eleventh, can't tell the year. Byzantium not visible.
Twelfth, 1138. Civil war. A few holdings lost, a few gained.
Thirteenth, 1138. Byzantium not visible.
Fourteenth, 1148. Mostly intact Byzantium. Can't see Anatolia. Has lost a few Greek holdings.
Fifteenth, 1148. Byzantium has grown a bit.
Sixteenth, 1168. Byzantium not visible.
Seventeenth, 1327. Civil war, most Eastern holdings lost.
Eighteenth, 1145. Byzantium not visible.
Nineteenth, 1310. Huge Byzantium
Twentieth, 1183. Small civil war. Mostly intact Byzantium.
If we then discard any where the player was involved or Byzantium cannot be seen:
First image, 1310, Byzantium has splintered quite a bit.
Second, 1121, Byzantium is dealing with a civil war it seems.
Third, 1177, can't see all of it, but looks like it is in a civil war.
Fourth, 1279, lost most of its Balkan holdings. Civil war. Lost some of its eastern holdings.
Fifth, can't tell the year but the Golden Horde is there, so probably 1250ish. Huge Byzantium.
Eight, 1121. Intact Byzantium.
Twelfth, 1138. Civil war. A few holdings lost, a few gained.
Fourteenth, 1148. Mostly intact Byzantium. Can't see Anatolia. Has lost a few Greek holdings.
Fifteenth, 1148. Byzantium has grown a bit.
Seventeenth, 1327. Civil war, most Eastern holdings lost.
Nineteenth, 1310. Huge Byzantium
Twentieth, 1183. Small civil war. Mostly intact Byzantium.
So what we see here is that in almost all the remaining 12 images Byzantium is dealing with civil war. One image with heavy splintering. Two where it has lost most of its eastern holdings (and another where we cannot see them).
Overall, 5 out of 12 I'd consider mostly intact. Three where it is facing major problems. Most of the images are too early to really tell anything.
Of the three images past 1300, it has splintered heavily in one, lost its eastern holdings in the second, but is huge in the 3rd.
Overall it seems the main problem is that the civil wars are too easily resolved, as while Byzantium seems to always descend into civil war, little happens as a result. The Muslim factions surrounding Byzantium should be more opportunistic, and the internal Byzantine factions should probably be more likely to vie for independence.