Yeah, would have to say my method isn't simplistic at all..
I shade so that other details stand out more, and I try to get a more.. lifelike appearence as far as shading goes, it's just the way I learned how to do it. I can understand why you thought it was messy... for that sprite it was pretty messy. Lots of details in a very confined space, but I did what I could to make it look as close to the battler as possible. Overall though, from the point of view you'd normally be looking at it, it looks good, at least I think so.
BTW, the one posted here was Blizzards slight alteration of the original. He did some editing in photoshop (I believe).
Might look a little cleaner pixel by pixel.
His alternate fits his needs though, so either way I'm happy. And good job on the down sprite, looks good. Also, the face down part of the sprite was originally Calintz's version, I altered it slightly to fit the color scheme better, but that's probably why the shading sooms a little... odd, especially around the shoulders.