Sepulchrave II
Legend
I don't think we have a single perspective on the Elves. In The Hobbit, they are very much presented as "airy-fairy" - whimsical, treacherous (in the case of the Silvan elves), and scant on any description of their actual appearance.Tolkien's Elves are not...whatever was happening in Jackson's films. They are not airy-fairy, they are Biblical or Shakespeareab figures of strength and tragic flaws.
In the LotR we still only see them through the lens of the Hobbits; they are very much depicted as Other, with their beauty, subtlety, superhuman faculties and insight. We have a sense of the tragedy of the High Elves - and their growing disconnection from Middle-Earth - but we don't have a sense of why; this is evident from the first encounter with Gildor: when he describes himself as an exile, we don't really have any context for that, until we dive (much) deeper into the legendarium. The Hobbits view the Elves with awe and reverence; the Rohirrim with fear and suspicion. Aragorn, despite his undoubted lore, in a sense seems all-too-willing to excuse their past misdeeds; although, he is enamoured of an Elf and was raised in Imladris - so maybe we should take his perspective with a pinch of propagandized salt too.
In The Silmarillion we begin to catch a glimpse of how the Noldor view themselves (and other Elves), but even this is fraught. It is a retelling of an "Age of Myth," suggesting layers of unreliable narration, translation, hyperbole and propaganda; within the context of LotR (or the Red Book of Westmarch), these are "stories from long ago." Again, I think this ambiguity is intentional, even in the earliest drafts by Tolkien (where Ælfwine journeys to Eressëa and learns the "true history" from the Elves), this notion of a dubious transmission is present.
The mythemes and components which comprise Tolkien's Elves draw primarily on the lios alfar and the huldrfolk; the Vanir and the Tuath Dé, overlayed with a Catholic or Biblical sensibility which reflects an increasing separation from God (with an occasional remission or "New Covenant"). In this sense, the Eldar have a quality of sacredness due to their time spent in Aman, whereas Middle-Earth is profane; this does not map perfectly to notions of Good and Evil; again, I think this ambiguity is intentional.
I don't see Shakespeare in Tolkien - at least, no more than Shakespeare has shaped all English literature; even the most tragic story, of Turin, doesn't hold a candle to Lear or Titus Andronicus in terms of its scope, or its willingness to engage with the worst facets of human action and motivation.
So when you assert that the RoP is faithful to the "deeper themes" in Tolkien, I respectfully disagree. I am enjoying the show, for what it's worth. But, for me, the characterization is weak; plot is contrived; dialogue is barely sophomoric with tedious archaisms; the Elves are just uninsightful humans with pointy ears and very prosaic motivations and teenage behavioural issues.
Is Jackson's trilogy more "faithful?" - no, not really. But I enjoyed that too.