Deciding on a religious symbol and using it in a cemetery is actually a pretty big deal, because in order for it to make sense it would have to be introduced in a shrine/church along with a back story.
Furthermore, because there are four gods we would have to decide on a symbol for each one, and it would have to integrate into the religion's background. Or if we made mana a sort of religion, then we would have to have a symbol for it which actually makes sense with the back story.
Also, if we used a symbol in this cemetery, it would imply that this particular religion is dominant in the area; or if we used multiple symbols in one cemetery it would imply that the multiple religions get along well enough so that they will bury their dead in the same area.
So in reality, deciding on a symbol is going to require fleshing out our back story! Which is good, because the back story is something that should be finished ASAP to make the whole world make sense.
