Personally, I think that if these storylines are given the Moria treatment (watch all worth of an expansion and 100s of quest progression turn to rubble in a rushed instance. everything is just falling apart in a few minutes) I'd rather the storylines just remain forgotten rather than be given a conclusion that isn't worthy of the story that lead up to them. Moria being the most extreme example I've seen, next to Game of Thrones' later seasons.
"...None of us would join the Grey Company if we felt its errand was not important enough to brave those risks. For my part, I will not give in to fear of the unknown. We all have our role to play, and I hope only that when I have played mine, the world will have been better for my having been in it.