I'm doing this as Eleanor, and I took Monastic Isolation so I'm not suffering too bad from it (I don't lose Religious pressure from losing my theological battles!) I'm getting Relics everywhere, and then using those to take over their cities! XD I built Mont St Michel, and ooooh I feel like I'm cheating, lol. I also make sure I spend all but one of my charges before I start looking for fights so they can die, lol.
So I'm spreading my religion and getting Relics, and both are helping me win with Loyalty XD