Just some suggestions about Great Moravia:
- from the start, most of the nobility was Christian, although lower classes were generally still pagan
- Bohemia was not always part of Great Moravia; the only moravian ruler who had real power over it was Svatopluk, so it would be better to make it totally independent (with the expetion of Svatopluk rulership, that is)
- it would be great if you could make an event chain about christianization of G. M. with contest of latin priests (generally catholics from Germany) and the orthodox church represented mostly by native priest preaching in old church slavonic (
Saints Cyril and Methodius were their teachers)
- the succesion system should be elective, as moravian magnates had great deal of independence (maybe it is possible to use a trait like "Born in Purple" to increase chances of Mojmirids to win it)
- as Hungary was not, in this time, inhabited by hungarians but avars (after all, Great Moravia was destroyd by hungarian raiders as soon as they came), it should be represented somehow (maybe via horde system?)
Oh, and if you make Bohemia independent, I could provide you with the names of dynasties and some rulers; but they should all be ruled by Premyslids. Also, although like in Great Moravia most of the nobility was christian, Premyslids were not;
Borivoj I. was baptised in 883; also, Bohemian nobility was mostly christian (as they are records of some of them being babtised in Regensburg), Premyslids were orthodox (as Borivoj was baptized by Svatopluk s priests).
Oh, and Borivoj was probably cousion of Svatopluk and a son to Rostislav who ruled before Svatopluk (Svatopluk was Rostislav s nephew - that is also why I suggest to change the succesion law).
I am not a programmer, so I really don t know what is possible, but I can imagine that it would be hard to do all I suggest - mainly all those events. But I am willing to help with all this as much as I can.