Companion piece for this and this.
There's so much wonderful storytelling in this piece (and in the entire triptych). The peace of the wilderness; Maglor protecting the boys. Maedhros, haunted, sitting up awake and conscious of the all-knowing light. And Eärendil, elevated near to the level of a deity himself, watching over the world he left behind. I do wonder what Eärendil thought of as he soared high above everything, covered in the magic fairy dust of the gods - whether he still should be considered an Elf, or something else entirely, neither human nor Ainur.
I wonder about Eärendil as well - the more I read the passages on the transformation, the more it seems to be that he becomes something so singular there is no way he can be counted among the elves anymore. But until I read your comment, I never thought about how close to an Ainu he might have become (Glorfindel is described as becoming something close to a maia in Tolkien's last writings).
Did Eärendil meld with the silmaril so that he received extraordinary power from the light of the Trees locked in it? There's always been a huge question mark over how he killed Ancalagon; one speculation was that he rammed the prow of Vingilot into the dragon, but that's kind of silly. Most guesses have something to do with his unleashing the silmaril. Since Morgoth was never able to harness its power for the centuries he sat in Angband with three then two of them in his crown, I agree something huge must have happened to Earendil. It's possibly the reason why his dwelling with Elwing is so isolated in the North; they've both become something so different from what they were before that they cannot live among people anymore.
It's pretty awesome but also really sad.
That parallel between Elwing and Eärendil is something I never noticed - both were transformed in a way that elevated them from, and separated them from their people. And I think both being half-elven ties in as well. They were forever caught between worlds with no place to go, and their descendants had to grapple with that all through the ages. But the two of them were able to (or perhaps forced to) transcend the cultural fetters that bound them. Would agree - awesome and also sad.