no dumb castle/town setup.
more unit variety (especially elite units)
no dumbass pope
no ridiculous religion rebellions in north africa making settlements uncontrollable.
more interesting factions
no gunpowder (lame having both gunpowder and swords)
no stupid mongol/timruid invasion mid campaign who have infinite money and guys but no provinces
no stupid provinces like the useless scandanavia being split into 3 parts
stupid americas segment.
black plague (is that really necessary, no.)
no stupid papacy states who basically run the whole campaign.
no stupid crap like "your faction leader must join the crusade", that crap is fkin lame.
in Medieval late campaign is feudal knights vs feudal dismounted knights.
retinue expansion actually makes sense relative to what's going on, my guy doesn't just become "bloodthirsy" for no reason.
cardinal votes are always crap and completely random.