it didn't slow me down at all, just makes reorganization within tedious.
I don't mind costs scaling, but most gains in piety are in lump sums, post crusade, handing out bishoprics, and donating. but because crusades got me holy relics, and therefore piety gain per month, everything is way more expensive? then counter-intuitively you should get rid of all piety gain per month items and traits and just holy war and donate to get papal points