» Mon May 21, 2012 9:05 am
There are a few things to consider. The killing of Almalexia (remember, while you may have killed Vivec during your playthrough, he is mentioned in Oblivion) is a great feat. However, it is mentioned many times that the tribunal is losing power while Dagoth Ur is gaining power, to the point that the three of them couldn't get to him in Red Mountain. On top of that, the heart of Lorkhan was destroyed and she had lost her divinity, so she was considerably weakened when she was killed. The same holds true for Dagoth Ur. You can only fight him after you destroyed his divinity.
As for the Avatar of Hircine, it's a test of skill. There's no indication that you're fighting Hircine at full strength and you can even choose how you want Hircine to fight beforehand.
While the Champion of Cyrodiil had no great singular feat during the main quest, he did enter Dagon's plane up to 60 or more times and killed thousands of Daedra and Dremora. His greatest achievements though, seems tied to his adventures outside the main quest. Umaril the Unfeathered and Mannimarco are fairly powerful wizards in Elder Scroll lore.
Of course, the greatest feat is defeating Jyggalag in Shivering Isles, and becoming Sheogorath. Unlike Hircine in Bloodmoon, you're probably fighting the deity itself, in his realm (which the Shivering Isles is, though it's been twisted by Sheogorath). There's also indications that Jyggalag may be particularly powerful, even for a Daedric Prince, as the other princes feared him.
On top of this, the Champion of Cyrodiil becomes the Madgod, a daedric prince. You may scoff at the weather changing power, but it's just a gameplay solution to show that you have power in the Shivering Isles beyond what you had before.