- What rhetorical level will we use?
- Archaic language? Modern language?
- Diff between dialog and voiceover/frame (if any)?
- Other issues?
I was distracted by all the other great threads forming on here, that I'm only just now getting to aroun to supplying my own opinion concerning the questions for the actual upcoming episode.
Rhetoric level is tricky because there are so many different levels within Tolkien own work. The Lord of the Rings films did an okay job at using the lines from the text as directly as they could and just smoothing them over here and there... The Hobbit did the same thing but were less consistent. However, because of the Hobbits, the later chronology, and even closer perspective in terms of the reader observing conversations between the characters, the Lord of the Rings have a naturally more modernized style of language compared to the Silmarillion anyways, film adaption or no.
I say keep as much what's represented in the text of the published Silmarillion verbatim, only smoothing out lines here or there when necessary for the purposes of clarity and screen-time economy; essentially a case by case basis. Any dialogue incorporated from earlier drafts would have to be converted to the rhetoric of the Silmarillion, as many of the drafts are even more archaic.
Overall, I see no reason to hand-hold a modern-day audience; I have always detested treating the audience like complete idiots instead of challenging them to actually use their brains for once. There's no reason movies should be dumbed-down just because they're targeted towards a mass market nor because they're a visual medium. Art shoud not be a slave to a perceived audience. People still watch period pieces, people still watch Shakespeare, they can handle the Silmarillion, especially when the text of the Silmarillion will be even more clear on screen when aided by addition of ques from the composition, music, acting, and even more subtitles that are absent in the book.
- How will we handle the chronology?
- Bounce back and forth between contemporaneous plots?
- Jump around in time?
In terms of chronology, I say just go in order, as was mostly done in the book, no need to make things more confusing. I'm not a fan of the frame narrative to begin with, but even if there were a frame, jumping back and forward to wouldn't really be necessary because all jumps in time could easily and more efficiently be conveyed through simple editing alone.
However, in my own attempts at scripting the Silmarillion I have found it better for the story to displace at least one storyline, that is the tale of 'Of Maeglin.' In the text of the book itself, it is somewhat displaced, but to have it where it is in the book would be too soon on screen in relation to the Fall of Gondolin, since it is a precursor of the events there.
I personally moved it so that it became a flashback in the second act of The Fall of Gondolin (after Tour has already arrived and before Maeglin's captivity by Melkor). True, this means his appearance at Gondlin while Hurin and Huor are there now precedes his former introduction, but having a backstroy for a then minor character would make little sense as a prelude into the tale of Turin Turamabar. Moving that backstory into the midst of the Fall of Gondolin allows for a more concentrated character study of Maeglin, since he really is the most interesting character of that part of the story and the main driving force leading up to the white city's fall. I could talk all day about Maeglin, especially concerning a film-adaptation version of him, so I will stop myself now.