I disagree that the difference in method of story telling necessarily makes it worse. I am one of the minority here that seems to have liked all the books, right through 11. Yes, some of the later books were slow paced. Yes, there were times when you wondered what had happened to the main characters. But for me what Jordan gave was not characterization or plot, but rather an entire world.
I became lost and immersed in a world that felt almost as complete and full of history as our own. I felt less like I was reading 'the adventures of a unlikely being who can do anything' and more as if I was catching glimpses of their lives in between news stories from all over the world. Without the side stories of the Aiel or the Atha'an Miere, we would have a less full world with less understanding of the universe that he created.
Paint me a thousand trees, Sketch me the outline of a forest, nay a world. Then let me fill it in with my own musing and imaginings. A good story in my opinion is one where you feel like you know the world well enough to wander into it on your own. That if you were dropped there yourself you could survive without worry.
Robert Jordan was not the best writer I have encountered. But he is on the shelf where I keep all of my favorites that I will read time and again.