Actually, Tolkien was a pretty bad writer, and I say that as one who loves LOTR as much as any nerd. What we have is a fantastic epic story, but a mediocre storyteller.
DT trumps LOTR in virtually all respects. Here we have an epic story, told by a master storyteller.
As far as W&G, I'm not sure where I'd place it, but it's in the better half of the series for me. I will agree, though, that the beginning of the "flashback" is abominably slow.