[Bêthberry]

His final plea to Aragorn, to 'go to Minas Tirith and save my people!' was, in my mind at least, an important factor in Aragorn's decision making from that point forth, as it gave him a tangible oath ('Be at peace! Minas Tirith shall not fall.') to fulfil rather than simply a doubtful destiny to look forward to.

I like how you relate this death to the plot, Son of Númenor. You provide a tangible reason and not simply opinion or personal preference (not to slam either, but they are tough to debate!).

Many of the deaths here concern derring do and heroic exploits. But I wonder if we could not step back and ask which death has the most bearing on a central concern of LOTR, the "gift" of man, mortality.

In this context, it seems to me that Arwen's death, recounted in Appendix A, part v, encapsulates most clearly the poignancy of this dilemma of death in man and elves. I would not call it "awesome" but certainly profoundly moving.

But Arwen went forth from the House, and the light of her eyes was quenched, and it seemed to her people that she had become cold and grey as nightfall in winter that comes without a star. Then she said fairwell to Eldarion, and to her daughters, and to all whom she had loved; and she went out from the city of Minas Tirith and passed away to the land of Lórien, and dwelt there alone under the fading trees until winter came. Galadriel had passed away and Celeborn also was gone, and the land was silent.

'There at last when the mallorn-leaves were falling, but spring was not yet come, she laid herself to rest upon Cerin Amroth; and there is her green grave, until the world is changed, and all the days of her life are utterly forgotten by men that come after, and elanor and niphredil bloom no more east of the Sea.

Oh, I weep as I read this, for all the unnumbered lives of women who have passed unremarked and unmemorialised in all the ages of history which are devoted to the accolades of men and their petty rivalries and their doings and gettings and spendings.

Concerning the significance of Arwen's death, Tolkien wrote in Letter #181:

The Incarnation of God is an infinitely greater thing than anything I would dare to write. Here I am only concerned with Death as part of the nature, physical and spiritual, of Man, and with Hope without guarantees. That is why I regard the tale of Arwen and Aragorn as the most important of the Appendices; it is part of the essential story and is only placed so, because it could not be worked into the main narrative without destroying its structure: which is planned to be 'hobbito-centric', that is, primarily a study of the ennoblement (or sanctification) of the humble.

Of course, this is just my own personal reading; there are many other deaths as stirring.