This was a great read! Your Miriel is a very believable and sympathetic character, trying to keep going in a world that is slowly becoming more dangerous and hostile to her. I love the little episode about her childhood (little Miriel is just adorable!), and Amandil's respect for the seagulls. Also, I love how you weave all these different references to different times and events into the story.
And this:
"The Elven-tongues and Adûnaic—once they had fit together to make the two halves of the world, like sea and sky. She remembered her father pointing to the constellations and teaching her their names: Menelmacar, Soronúmë, Telumendil. And then in Adûnaic: Minalzagar, Narâkadûn, Rakuzîr. Now half the world was sheered away. Since Ar-Pharazôn had made her his wife, none had called her by any name but Zimraphel."
- I think that is my favourite bit in the whole story. I can only imagine how it must be, to lose a language you grew up with like that; in a way, they are their own little worlds, and Miriel has lost half of hers.

And lastly, I don't think the poetry is awkward at all - in fact, I am just a little bit in awe :)