Elric was cult reading in my first D&D group, and my husband liked Moorcock so much when we met, I had to read the entire 22-book Eternal Champion cycle in the order he specified early in our relationship. The intensity has worn off, but he still has his own set of shelves in the Collections Room (with pulps, Lovecraft, and Sherlock Holmes). I haven't read much else of Moorcock's. but that one-big-swallow reading of the EC left me feeling qualified to say that Elric is like the "hit single" off a good album - not the best track, because the best track is less accessible to mainstream audiences than the catchy mediocrity of the hit. The first Corum series was the best track IMHO.
People who don't enjoy discussing literature in a critical way can skip the rest of this post.
When helping out at a Renfaire during the same era, a Rennie who doubled as a schoolteacher, in one of those long academic discussions you have with Rennies when it's raining or at night after the customers go home, contrasted Moorcock with Tolkien as a talented hackwriter vs. a non-talented literary writer. The point was not to declare one better than the other, but to distinguish what they did and how they did it and show that writing in the same genre did not necessarily make them directly comparable. I think the distinction is valid, but not definitive. This conversation led me both to regard hackwriters with more respect than I was trained to and to view the issue of talent more realisticly. This is also about the time that I began to recognize the irrelavance of hierarchical judgements about literature.
Allt this makes Moorcock a pretty important writer to me, even though I don't enjoy his work all that much.