I havn't had a chance to keep up with all this, but some suggestions that I've thought about doing...
A. wife traits should effect all married charactor of all faction, it's pretty obviously dumb that only Non-Muslim royalties married to princeess are effected by their wifes
obviously this can lead to other interesting traits, such as Muslim Cumans may have multiple wife trait or something (increase chance of having children, maybe lead to decrease in personal secruity though as Osama Bin Laden would attest
)
B.Cultural trait, for example cumans named charactors would inherently have movement bonus, Byzantiums building bonus, Italian trade bonus etc etc.