The only thing I might change in the poll is Cilician Armenia switched with Ireland. For some reason I was thinking Cilician Armenia had more impact in 1200s and while the region did not become a kingdom until 1198 it did have some impacts earlier. Ireland while nominally independent was never organized and would be similar to some other areas of the map where control was nebulous and never the center of any conquests.
Abassids I've been a fan of for a long time having included but in the early era its more difficult as they truly were vassals for most of 1100s and MTW2 does not model that relationship very well as at start of a campaign can only be allies- I've wondered if there is a way to script it though so on turn 2 relationships are changed to vassal along with a notice of the historical situation and ways to break vassalage.
For the current late campaign I agree Abassids totally as they actually had a large impact 1160-1260 and if not for Mongols could have had a very strong revival. Maybe even an argument around 1136 but they did not really definitely break vassal status until defeating the Seljuk siege in 1157 and the Caliph which was responsible for the rise of Abassids died in 1160 with his Heirs of varying capability.
I like Volga Bulgars but it would only make sense in the context of also adding Suzdal or some other Rus faction which is not going to happen. I think enough is know to make a basic roster for them.
As for Sultanate of Rum- here I disagree, the current void in Anatolia is very unrealistic.
I can see removing Timurids giving 3 open factions as very likely in SS, Georgia, Serbia, Sultanate of Rum would be my choices in early era. Abassids and Mosul would be my 4th and 5th if that ever happened but I doubt Lithuania would be removed- its too fun and would also create a huge power vacuum in Baltic. Teutons... I'd actually wish Teutons to be spawning a bit more powerfully.