And in a world where nonhuman people exist, but it might still be necessary to refer to an adult male person of unspecified species, one would expect that most languages would not contain that ambiguity. In fact, in such a world, it might be uncommon for a language to even have any word for “specifically human adult male”, and you might have to use constructions like “human man” every time you want to refer to such.
Thank you for answering the main question. I take the liberty of repeating the bonus question and the side note non-canon question, in case anyone cares to elucidate.
“Hinder me? Thou fool. No living man may hinder me!” - Witch King
“This should say ‘No, living man may hinder me.’” - Lionel Hutz
Or perhaps Glorfindel foresaw more detail than he described, and deliberately phrased it ambiguously, knowing that the Witch-King would learn of his prophecy. As a consequence, the Witch-King arrogantly dismissed the threat when it finally arrived, giving Merry and Éowyn their opening to strike him down.
Which is the classic self-fulfilling prophecy, which is pretty much what the geas (if you’re Irish) or geasa (if you’re Welsh) tends to be, in those tales. It’s twisted a bit here, because usually such a tragic flaw is ascribed to the hero, but here it is an opening in the armor, so to speak. Like Smaug’s broken scale, that sort of thing.
Really, the heroes in Tolkien’s tales don’t have too many weaknesses, do they? They face incredible odds and foes, but generally the biggest obstacle seems to be temporary moments of self-doubt.
Apart from the Ring, of course. That bugger is something else.
At least one of them headed back to Mordor with the bad news, and Frodo & Sam saw it:
“As it went it sent out a long shrill cry, the voice of a Nazgûl; but this cry no longer held any terror for them: it was a cry of woe and dismay, ill tidings for the Dark Tower. The Lord of the Ring-wraiths had met his doom.”
The remaining Nazgul trailed Aragorn’s army as it made it’s way to the Black Gate, though they stayed high enough that only Legolas could see them. Then they were hovering over the Black Gate when the army arrived, and took part in the battle. But when Frodo put on the Ring, and Sauron realized how badly he had screwed the pooch, he summoned them back to try to salvage things:
“At his summons, wheeling with a rending cry, in a last desperate race there flew, faster than the winds, the Nazgûl, the Ringwraiths, and with a storm of wings they hurtled southwards to Mount Doom.”
But too late:
“And into the heart of the storm, with a cry that pierced all other sounds, tearing the clouds asunder, the Nazgûl came, shooting like flaming bolts, as caught in the fiery ruin of hill and sky they crackled, withered, and went out.”
Aragorn and Luthien are the only two I can think of that are pretty flawless, who else were you thinking of? Even Sam had his hatred of Smeagol, minor as that flaw may be, and Faramir doesn’t quite count as a hero I’d say.
At least in the movies, Arwen is in the category I mentioned; she temporarily gives in to Elrond’s desire to see her go to the Undying Lands and abandon Aragorn, but overcomes it. Legolas has a moment of doubt before the battle of Helm’s Deep, but otherwise he’s pretty flawless. Gimli is a little prideful, but that’s apparently common for Dwarves. Merry I would place a bit higher than Pippin, only because Pippin is a bit more naive than Merry. Eowyn’s only flaw seems to be that she’s a bit of a hopeless romantic at first. Theoden’s flaw (after being released from Saruman) is a bit of pride, but he overcomes that, too. Treebeard is just really slow to realize his responsibility and to act on it.
I guess the point here being none of these are TRAGIC flaws, leading to downfall, as you might see in Hamlet or Macbeth or Greek Tragedies. Everyone who succumbs to their weaknesses are pretty much villains. Possibly questionable in this regard: Grima Wormtongue. I think Grima could have been redeemed eventually. But, you know, he was named “Wormtongue” so that doesn’t bode well, does it?
Oh, and of course Thorin. Thorin is maybe the only real tragic hero in all the tales I can think of. He redeems himself but he also is the one who brings suffering upon himself and those he loves.
None of those are the heroes, though. The heroes of Lord Of The Rings are Aragorn and - technically - Frodo, but really Sam.
As for the others you mention, Arwen, Legolas and Gimli barely have any characterisation. Merry and Pippin are effectively naive, rich teenagers who have no idea what they’re getting into, and Pippin nearly ruins everything by looking into the Palantir. They do redeem themselves on returning to the Shire - probably the most grievous change in the films was removing that part, and destroying the character arcs of Merry, Pippin, Saruman and Grima (who does, in fact, redeem himself at the last).
Theoden listened to Grima in the first place, again nearly ruining everything, instead of listening to his family. Treebeard, like Bombadil, was too tied to one location and let his wilful ignorance lead to problems on his borders. Bombadil may have been that way by nature, but Treebeard was so by choice.
One could argue whether Gandalf’s trusting nature is a flaw - he could have possibly stopped Saruman earlier, but (as he points out) had he not allowed Smeagol to live, Sauron would have won.
As for tragic heroes, Turin Turambar is possibly the most tragic in all of literature, unless you count Feanor as a hero. Even Beren repeatedly needed help to achieve his goal. Isildur, of course, failed in the same way Frodo did, but with less excuse and worse consequences. Then there’s Ar-Pharazon - undoubtedly the greatest and most powerful King of Men in the legendarium, whose armies defeated and captured Sauron, but his hubris led to the destruction of Numenor and the hiding of Valinor, probably the greatest tragedy that happened to Men.
Really, The Lord Of The Rings is only one small story in Tolkien’s creation, there are many more heroes, villains, and al things in between, and very few of them are solely good or evil, with the exception of Morgoth and maybe Ungoliant.
In Luthien’s case, as Tolkien himself acknowleded that his inspiration for Luthien was his wife, Edith, it’s not too surprising. 
The other eight were not all present at that battle, though it’s not certain how many were. At least two were likely operating out of Dol Goldur, commanding attacks in the northern theatre. The Witch-King fell on March 15th; on this same date, attacks were launched from Dol Goldur on Lothlórien and Thranduil’s realm in Mirkwood. Another attack on Lothlórien came on the 22nd. Dale was attacked on the 17th, beginning the Siege of Erebor. It’s possible that no Nazgul were involved in the attack on Dale, but I think it likely that at least one was involved in each attack on an elven domain. So, here’s a rough outline of where I think they were and when:
March 15 (before WK’s fall) - Witch-King and 5 or 6 others are at Gondor. Khamûl (sort of the second-in command, and the one Sauron left in charge of Dol Goldur) and one other are leading attacks in Mirkwood and Lothlórien. (If a third was present, he was likely supporting the assault on Lothlórien.) One diverts from Gondor to Cirith Ungol, perhaps drawn by Sam’s use of the Ring; he arrives before Sam and Frodo saw signs of the Witch-King’s defeat.
March 15 (after WK’s fall) - The remaining Nazgul at Gondor withdraw from the battle. One flies for Barad-dûr to report; Sam and Frodo hear him pass overhead. The Nazgul at Cirith Ungol, finding the fortress empty and the pass unguarded, begins to search the area, and likely continues to do so until recalled.
March 16 - Khamûl returns to Dol Goldur. The other Nazgul with him (whether 1 or 2) are recalled to Gondor.
March 17 - With only one Nazgul remaining in the northern theatre, the attack on Dale proceeds without air support. Khamûl remains in Dol Goldur, preparing for a final assault on Lothlórien. One Nazgul remains near Cirith Ungol, probably trying to replace its garrison while also searching for whoever trashed the place. The messenger returns to Gondor, and the 6 watch, trying to determine what the next move will be.
March 19 - 6 Nazgul shadow the Host of the West as it leaves Gondor. Khamûl is still consolidating his forces. Harried Middle-Management Nazgul in Cirith Ungol is dealing with OR (Orcish Relations) problems.
March 22 - Khamûl leads the final assault on Lothlórien, and, having learned that the third time is not the charm, is recalled. The 6 may be involved in the ambush on the Host of the West, but it’s only a feint, so it doesn’t really matter. HMMN, having dealt with his personnel issues and not found any sneaky hobbitses, joins them.
March 23 - It’s pretty obvious where the Host is going at this point. After watching a contingent break away to the south, the Nazgul fall back to the Black Gate to wait. They probably make HMMN stay and keep an eye on the Host because they think he’s been goldbricking up in the pass for the last week.
March 24 - Khamûl and HMMN join the others at the Black Gate.
March 25 - All 8 remaining Nazgul are present at the Battle of the Morannon until Frodo puts on the ring and their boss freaks out. They bolt for Mount Doom and arrive just in time to crash and burn.
I’m sure you can head-canon some explanation, but no, it doesn’t really make sense. Potential explanations are that the wraiths haven’t gained the strength they have ~70 years later in LOTR and haven’t yet achieved any physical form. Elrond (with his Elven ring) and Saruman are able to (something something) “stun” them or briefly knock their spirit out of the World, and it takes them a few seconds to recover and come back. When they stop coming back, it’s because Sauron has summoned them to join him for the final battle, not because they are unable.
Excellent!
Odd, isn’t it, that the Witch-King knew all about what Glorfindel said?
If my guess about Glorfindel’s prophecy being deliberately self-fulfilling is correct, Glorfindel could have taken steps to make sure that word got around. If not, well, he’s a sorcerer, and he had a long time to find out about it.
Well yeah. Heroes strive and overcome their flaws, villains succumb to them. Theme.
And, y’know, that Boromir guy…
You could make a case for Gollum/Smeagol too. But yeah, as has been pointed out, most of your examples don’t HAVE characterization or character arcs to speak of.
He had a copy of the book.
What about Denethor?
Denethor cracked under unbearable strain. He was, as far as he knew, the only real line of defence against the Sauron, and Sauron had been lying to him and manipulating him through the palantir. Add to that his belief that Aragorn was coming to usurp him, after Aragorn had to an extent taken his place in his father’s affections, and led his son to his death. And the early death of his wife. Yes, Denethor failed at the end, but that he held on as long as he did was remarkable. Compare him to Theoden - a King where Denethor was “just” a Steward - who cracked just from second-hand words of one less powerful than Sauron. And Theoden was not a weak man.
The films portrayed Denethor (and Faramir) extremely badly.
Not too surprising:
- WK taunts King Eärnur to come at him, bro.
- Glorfindel tells Eärnur not to take the bait, WK’s not going to fall by the hand of men.
- Eärnur takes the bait, rides after the WK, is never seen again.
There’s plenty of narrative room for the Witch King to have heard some form of the prophecy from Eärnur himself. Pretty unpleasant narrative room, but Team Sauron was always fond of playing with its food.