some of them do have specific attitudes and responces, and they do in some complicated little way tie into unit and building creation.

muslim devout is like catholic crusader, i think, the faction is more llikely to jihad, but it doesn't prevent or in any way control other factions from doing it, so you'd never know...

only support limit has obvious messages, and i've only seen it really when used when a faction resurges with a massive amry in to just one province. poverty stricken and support limit are also good descriptions of any one provice faction, one province rarely gives enough cash to support the heirs, and AI never dispands once a prince "dies"...