Grant your provinces seat in parliament and bribe them to vote on issues that strengthen your nation.
Theocracies choose their successors from 6 different alternatives, such as an influential preacher or a noble's son. Protestants acquire the ability to create their own national church by gaining religious tradition, whilst Buddhists must maintain balance between high and low karma (high karma ruler becomes detached from the world, while a low karma ruler loses trust of their soldiers).