Kings and the Royal Line

Why was Elros elected as the first King in Numenor, and not some other lord of the Edainic Houses? Why would he take precedence? And what happened to the other lineages, like the lineage of Hador Goldenhead?

Speaking of Hador, since the Dunedain are derived from the Ancient Edainic Tribes, including the House of Hador, how come we have no blond Dunedain?