Still the same thing, any admin ideas would do the job. You sink all your mana into ideas, you start to be far enough to westernize.
I love to westernize as Poland since you get ahead on everything. A good order could be : Religious, Aristocratic, Diplomatic, Administrative, and whatever.
Also, religious ideas allow you to convert both religion and culture early in game. You don't get any trouble, even after forming the PLC. And there are random events that covert a city, whatever his basetax is.
However the real strenght of PLC is his position. If you manage it well, you can crush Ottomans from start and get BYZ. Too bad I can't do thi in MP, people would probably ragequit if they see a 100+ forcelimit before 1500 hahaha.