As a general rule when designing new cults or new sub cults, take the great god of a Rune as a benchmark for what can be done. For example, Humakt is THE god of the Death Rune. The second biggest god associated with Death is probably Zorak Zoran – and every time he tries to use Sever Spirit he must permanently lose three Rune points! Chalana Arroy is THE goddess of Healing. Nobody has a better Resurrection spell than her.
And so on.
For gods that are purely local importance, generally don’t give them a vast array of powerful spells. Zola Fel has almost no presence beyond the valley. Yinkin is a cat god. Other than a few cat things, there’s not much to him.
So for example, if I want to create a story about how Orlanth used Death to kill Yelm, that subcult might provide access to one-use Sever Spirit, but nothing more.
Same thing with myths. Don’t give a lesser god a greater cosmic role in a particular area than the god of that Rune or activity. Instead, let those lesser gods do something that perhaps brings that down to a smaller more intimate scale. Make use of some of those funky little Rune spells in the Red Book of Magic you don’t normally ever get to see.
