[Legate of Amon Lanc]

Nah, it doesn't sound that bad, Mugwump. Personally I had no idea when I saw the riddle and didn't feel like starting to think about something deeply for an hour. However, why not to make a little brainstorming, as long as it may give anybody a hint.

Your conclusions here made me think of Gaffer, for that matter. He was warming his hands by the fire, but that was in the Scouring of the Shire - when it comes to that, nobody says that the answer itself has anything to do with the Ringbearer at all. I didn't get it if the "one" is supposed to be "the one" (whom we know from somewhere before, for example from the first four hints) or if it is a new one, who is defined only by being "one in the Ringbearer's place". Which could be Bilbo, Gandalf, Frodo, also basically any silly Sackville-Baggins or young hobbit knocking on the floor, or even a Dwarf. (For that matter, even though I think the place is supposed to be Bag End, nobody says the Ringbearer needs to be Bilbo/Frodo. But most likely it is.)

Also, the initial impression I have is that we get something (four first letters?) from the start and we need to complete it with the rest.

Somehow, Samwise could fit there, but not completely. Once again the question is if the final answer is related at all to the riddle's theme (but it probably should).