As I’ve noted before, the Iranian political system is based on a bargain: the Revolutionary Guards get impunity, lots of money, and a religious justification for their thuggish behavior, while the religious leaders get the street muscle they need to keep Allah happy. The deal, ironically enough, resembles the tax cut for reactionary social policy agreement that keeps the GOP reasonably united.
There has been a lot of speculation that Khamenei’s death will result in a shift of power to the thugs. I think that will happen, but only within the framework of the existing deal. That’s what happened to the GOP, where the Reactionaries now drive the train and the PBPs follow; don’t expect anything different in Iran.