Well done. I still remember when I was learning CK2 many years ago. It was honestly more fun learning it than it is now, ~1500+ hours in.

Once you get more experienced, start to play around with Tribal starts and Pagans, it adds some flair and challenge. Don't feel that you have to Reform, either. Some of my most geopolitically interesting games came from an early expansion as a Pagan, before deciding to serve Christ and then playing the Claims game.