I seem to gravitate toward finding the most significant character in Arda, and there are quite a few. Is it Beren and Luthien, as they represent the last trace of light in the darkest time of Middle Earth? Or Feanor, as the greatest of all the Children of Illuvatar? Or Turin because of his Christ-like suffering and right of meeting Melkor in battle in The End at Dagor Dagorath?
Who knows, but at the moment, I am placing my attention on Eärendil. He was the original character that Tolkien began with in The Cottage of Lost Play (History of Middle Earth 1), and represents all bloodlines (Men, Elves, Maiar) that sits at the nexus of the old and new worlds at the end of the First Age.
It will be fun to uncover the symbolism of Eärendil and look for traces of this character in other myths.