There's the question, who would replace Cayde? Only Ikora and Vuvuzela have obvious replacements if they died, imo. I think its obvious that Lord Salad-bar would replace Vuvuzela, and Osiris, would replace Ikora. But what about Cayde? Efrideet, Anna Bray, Shiro-4? Honestly, I could see it being Shiro-4 being that Shiro, was Cayde's protégé and is trusted by the vanguard.