I'm also fine with Orodreth never being captured. But I have always found his behavior ... not just weak, but foolish or even stupid. He goes farther than Turgon, IMO, by not even hiding from Morgoth. And Turgon's pride doesn't seem to fit as well with Orodreth. I would want some way to depict him that doesn't make him look stupid.
@cellardur , what's your concept of Orodreth as a character? I agree that he's weak and not very assertive. But I'm wondering how you conceptualize his decision-making around taking Turin's advice over Ulmo's.
Edit: I ask that in curiosity and hope that you'll have ideas that'd be helpful. Not intended to be hostile.
And in regard to Enemy storylines and Hildorien, I propose this:
Ep 2 or 3: Morgoth leaves to visit Hildorien. He immediately returns because scaring the crap out of Men doesn't help his goal of corrupting them.
Ep 3: He immediately sends "Annatar".
Eps 3-4: Sauron stays in Hildorien while Morgoth handles the spies. Learning that they've scheduled Mereth Aderthad, he calls Sauron back.
Eps 5-6: Sauron goes to Mereth Aderthad and oversees the spying for a while, briefly visiting Hildorien once or twice more as "Annatar".
Ep 6 or 7: Morgoth visits Hildorien with the golden armor and Silmarils, while causing a solar eclipse, or putting a really big dark cloud over the Sun. ('Eclipse' is seen from Beleriand.) Then he leaves them to build a temple, and sends Fankil to watch them.
Ep 8: Morgoth starts Dagor Aglareb at some point after his return.