Whose death do you think was the most unfair?

In theory, Tieru's spirit could have appeared to Nicholas just as it appeared to Agrael, and then Nicholas, like Agrael-Raelag, would have done everything to save the world because he loved Isabel just as much as Agrael.

Then, on the one hand, everything would have been simpler; Markal would have gone to war against the Empire, and many of the inhabitants of Ashan would have survived, but how could he have negotiated with Zehir to conduct the ritual if he "disliked" the mages because of Cyrus's cowardice, who would have been alive then? So, everything is very ambiguous.