Normally I wouldn't respond to anything on a thread like this, but I'm an English teacher and I about busted up laughing at this summary... The Tempest is a comedic romance, not a traditional Shakespearean tragedy, and what happened to Amaurot definitely does not map to the plot of The Tempest, which is not about a powerful wizard's powers going awry at all? (In fact, it's about a wizard using his power/enslaved spirits to seek justice against those who wronged him... which has shades of Zodiark seeking vengeance against Hydaelyn to it...)
If anything, Emet probably qualifies as an analog for The Tempest's Ariel or Caliban, magical beings who have been enslaved to serve the powerful wizard Prospero--sometimes these two agree to the things they are asked, but sometimes they are forced to act against their own will in Prospero's quest to return himself to his former glory. Ariel and Caliban together can be seen as an analogy for the way Emet views himself--as the "good" spirit--versus how we, the heroes, view him--as the "evil" spirit.
In terms of whether or not Emet qualifies as a tragic character, if we're talking in classic Greek dramatic traits, then yes, he probably does, because one of the central elements of a tragic hero is that their own flaws contribute to the tragedy they're stuck in. Characters in tragedies exhibit "fatal flaws" which contribute to their falls from grace. As you mention, hubris itself is a fatal flaw, and Emet's pride in his people and belief that his people's way of life is superior is what contributes immensely to his inability to allow Amaurot to fade into the past--he cannot accept the current races as the new inheritors of the star in part because of his overbearing pride and otherwise flawed character. Thus, he orchestrates the collapse of his own dream by failing to embrace change. Likewise, there's also tons of dramatic irony in that he insists his people were superior to the current races because of their peaceful and self-sacrificing ways... while he himself embraces violence to achieve his goal. The very fact that he can't fully identify the paradox/disconnect between what he's aiming for and his means of achieving that goal is what creates the tragedy. Tragedy also thrives on an element of inevitability--Emet cannot choose any other path than the one he ended up on in the game, in part because he's tempered and in part because he's just a flawed character, as I mentioned before. He was always going to end exactly where he did, and the conflict between himself and the WoL was unavoidable. Those indeed are all the really necessary ingredients for tragedy, at least in traditional terms.
A better topic might have been "Emet is unforgivable" which is probably an easier argument to win...