never said that shinigami NEED to be dead, fullbring is a whole other case but Quincy were introduced back than as a type of Humans in the living world who developed their powers to fight hollows.
it was my understanding till now that they would be living humans. i mean ok when kubo wants to pull of now that they can be dead and yet still "live" on with Qunicy powers whats bout the whole bunch of Quncy the shinigami killed what about ichidas grandfather.
of course it could be that shinigami controll whats happening with the spirits of the dead since they decide if they go to SS or Hell.
but if thats the case y dont send the sucker to Hell when he died is normal human death.
this whole bunch just seems to me like bad storytelling.
well its still possible that the leader isnt Quncy at all and just controlling leading them like aizen with the arrancar