I finally finished the anime series, and I think I may have underestimated the season.
What's interesting in this series was how Xanadu ended up as the product of the thousand years of war between the two sides, although the efforts of the people of the present were the ones who really made the change. From gods to denizens to Flame Haze to humans, all made their respective efforts to do what they can. Everyone and no one is a hero.
It's like what they say: peace is the consensus of the many, while love is the consensus of two. However, the free will of the Flame Haze and Crimson Denizens will continue to be a threat to the peace in Xanadu. Shana and Yuji's love story will continue on, with more challenges awaiting them.
What's unfortunate is that Kazumi would live most of her life with the memories of everything that happened in her heart, and that she may never be able to share those memories with anyone else. On the other hand, Ike should start trying to date Yukari sometime.