I've always been bothered by the Valar's characterization. For all that they're supposed to be lords and protectors of Arda, they don't exactly do the best job of it. I'm willing to glance over their original effort to capture Morgoth (they nearly destroyed the earth that time), but every other time they're most needed, they're either nowhere to be found, or fail utterly. They can't see through Ungoliant's darkness (they shouldn't need to; they're demigods — just lift up into the atmosphere and fly over the cloud if you have to). And while Feanor was hardly a saint himself, he's the only one who ever points out that they failed to keep Valinor safe from her rampage. Then there was the War of Wrath — it took hundreds of years for them to send help across to Middle-earth, and they basically let Sauron go (look how that turned out). Then they refuse to even speak to Tar-Palantir, even when he truly repents of his people's sins, which borders on outright hypocrisy — especially when you consider that any of his followers who weren't lucky enough to flee on the nine ships went down with the King's Men. In other words: the good suffer for the sins of the evil. (Admittedly that was Eru's doing, but the Valar never took action against Sauron or the King's Men in the first place.) It isn't until the Second Age (I think?) that they bothered to send the Istari to Middle-earth, which might have been of more help if they'd sent them a few thousand years sooner. And of course, the elephant in the room — they're never punished for their actions (or lack thereof).
The Valar's primary job was to make the world ready for the Children to arrive, but they could only do so much. After the Marring, they decided to prioritize protecting the Eldar and moving them to Aman (as they wouldn't last forever in Middle-earth once it was Marred), even after Morgoth was captured. While powerful and granted certain kinds of insights, they're closer to angels than gods, in a way. Manwë couldn't perceive Morgoth's evil when he faked repentance, not even Varda's stars could penetrate that much raw darkness, and Nienna couldn't cry the Trees back to life (even if she could get a flower and a fruit to light the sky). So they basically decided to be hands off. It's also more-or-less implied that Eru is also the same way, with the Akallabêth/Downfall of Númenor being the only exception. This is a narrative from the perspective of Elves and Men (mostly Elves), who even consider their guiding angels' motives and actions inscrutable (the Music of the Ainur being pretty much a metaphor for what may have actually happened), or try and assign their own meaning; we can't know for sure. Also, if correctly recalled, the Wizards didn't arrive in Middle-earth until the middle of the Third Age, probably because some Valar had an insightful flash that Sauron wasn't completely gone from the world, and didn't want to sink another continent into the sea by calling on Eru or intervening themselves.
Here's a silly one: Did Luthien's ear shape change when she returned from Mandos to Middle-earth as a mortal? For that matter: were she and Beren resurrected in the same bodies or different ones? Was Beren's hand restored? Did they just awaken in Middle-earth or have to sail there from Mandos?
Most probably, they travelled to the Halls of Mandos in spirit only, while their bodies remained in Middle Earth.
The Elves don't actually have pointy ears. The difference between Elves and Men is almost entirely spiritual. The only physical differences are height (Elves are taller) and prettiness (Elves are much better looking than humans).
There are some references to elves having pointed ears in Tolkien's writing, but that's just a minor physical detail; the real difference between the two races is spiritual.
Geographically, I am bothered. If Middle Earth and Aman were connected by The Grinding Ice, why wouldn't the forces of the Valar use that path to make a surprise assault on Morgoth during the War of Wrath? Shouldn't that be an easier route to use?
Why didn't US forces in WWII just march across the polar icecap to Europe instead of using troopships? Same answer.
It's mentioned in the earlier sections of the text that the Helcaraxë is not exactly an easy trip. It's bitterly cold, lacks food(which they would thus have to take with them and baggage trains across fields of snow and ice are far more difficult to handle than supply ships amongst a convoy), it is effectively a constantly shifting glacier making any kind of reliable pre-planned route almost impossible, the terrain is constantly shifting and is implied to a be under regular, if not perpetual assault from snowstorms. The oversea journey, especially angelically enhanced for ease of passage was both faster and easier with much less risk of casualties along the way.
I know its mentioned somewhere that during the journey, many elves died along the way from being crushed beneath suddenly shifting ice. which made me picture it less as a glacier and more a densely pack group of icebergs, all constantly moving about. Its a mark of Fingolfins leadership that he brought as much of his host across as he did.
Besides, when you have Manwe the Vala of Fair Winds and Ulmo the Vala of Following Seas behind you, the sea passage ought to be pretty smooth.
How were the Naugrim able to assassinate Thingol in his own realm and get away with it? Isn't his wife supposed to be a very powerful Maia?
Because they were invited as trusted guests and had free rein in the forges and treasure chambers. They killed Thingol when he was alone and defenceless. The Gridle of Melian doesn't restrict people's movements within Doriath or prevent them from leaving. Melian is not omnipotent or omniscient and she can't guard her husband every minute.
Why didn't Melian, Melkor, the Noldor, etc. trying doing anything about Ungoliant and her offspring? I know that fighting a horde of demonic spiders isn't exactly a cakewalk, but you'd think that one of them would actually try to confront them instead of letting them scurry around Nan Dungortheb. Ungoliant is an enemy of the Valar, poisoned the Two Trees, helped Melkor steal the Silmarils, and tried killing Melkor over those same Silmarils. You'd think that would send half of Beleriand after her. Sure, Melian did set up that Girdle to keep Ungoliant and other enemies out of her realm, but how come the Noldor didn't try going in there with their enchanted blades to chop the spiders up? Since Ungoliant's webs can be destroyed by fire, why didn't Melkor send any fire-drakes and Balrogs to burn the place down?
Ungoliant's brood were so dangerous that neither the elves nor Morgoth's people wanted to provoke them needlessly. They seemed to be content to stick to Nan Dungortheb for the most part, so it was less trouble to just set a watch on the land than try to invade it. Especially since it was essentially a no-man's land between Melian and Morgoth's spheres of influence and their magic mixing together turned the region nightmarish and nigh impossible to navigate, giant spiders or no giant spiders.
After producing her offspring in the Ered Gorgoroth, how was Ungoliant able to escape into the South? Those mountains are smack-dab in the middle of Beleriand and surrounded on all sides by lands owned by Elves, Dwarves, Men, and the servants of Morgoth. Surely someone would notice a giant, light-devouring demonic spider (or if she's using her Unlight, an impenetrable black cloud) passing through their territory, especially when those lands are going to be on high-alert due to the war.
You can't cut off a giant region like Beleriand from all travel, no matter how strong forces you possess, and the elves were already stretched thin against Morgoth's forces. Not to mention that Ungoliant can cross even highest mountain peaks with ease and has proven herself incredibly formidable in battle. Better to just let her pass, as long as she's not trying to settle in your home, than to risk facing her head on. Not to mention that she could have first gone to east and traversed around the elvish territories entirely, if she felt like it.
Eru isn't opposed to the Ainur having their own ideas of what to create, as we see from Aule and Yavanna creating the Dwarves and Ents respectively; the problem with Morgoth's initial desires was that he wanted to screw up what everyone else was doing in favour of his own design. So what might have happened if, instead of looking for the Secret Fire out on his own, he'd just gone and asked Eru, "Hey, dad, can I have the power to create a universe like you want to do?" Would Eru have let him do his own thing if he'd just asked and not forced anyone else to go along with it?
Morgoth's major malfunction has more to do with how he resents not being able to create something beyond the scope of Eru. Eru is effectively the infinity of creation, encompassing everything that was is, will be, and is possible (Can God create a weight so heavy that even They can't move it?), and Morgoth doesn't like the idea that as powerful as he is, he can't exceed the bounds of infinity. He didn't seek to complement the harmony of the Music with the occasional jazzy flair; he was trying to make it a murky mess with his chaotic themes. He had decided as far back as the Music that if he could not go beyond Eru, he might as well just ruin it for everybody; Eru chiding him that even his attempts at ruining everything were part of the plan or were the result of Eru allowing such chaos to exist just made him more hateful. He was never going to be pleased as long as Ea existed.
Maybe I missed something in the story, but something's been bothering me about Morgoth's curse on the Children of Hurin; if such a curse was easy to place on one family, then why the hell didn't Morgoth place a curse on all of his enemies? The Noldor? Every Man opposed to him? He could've defeated all of them in one fell swoop. Of course the simple answer is the already-known theory that there was no curse and all the misfortune that befell Turin was due to his own poor choices and jerkass-ery, but if that was the case then why make such a big deal about the supposed "curse" in the first place?
Morgoth is strong evil, but still only a Valar of lesser stature than the One (even if by a relatively small margin). His curse is more indirect than anything else—the Orc raids that separated the family, Glaurung sacking Dorthonion and keeping the pressure on Turin, and so on. This is less of a directed spiritual/magical influence, and has more to do with Morgoth putting the effort of his military forces, his dragon-breeding, and his inexorable will on the Children of Húrin. Plus, at this point, Morgoth was permanently crippled by Fingolfin; he wasn't going to get directly involved in the war again.