The nice thing is, they think that they need Orpheus for the rebellion, but they don't. If Orpheus sacrifices himself, Lae'zel and Voss lead a perfectly good revolution without him. I like this much better because instead of blindly following some prophet, the rebellion grows because other githyanki can be convinced to their cause. It would be nicer if Orpheus didn't have to die for this - poor guy had a rough couple of centuries - but I do prefer to have the rebellion led by ordinary githyanki, as this fits better with the overall theme of the story.