I don't think the admiration of Shawn Michaels is based on him being the best at any particular aspect of wrestling, but that he's very good at every aspect of professional wrestling. Its the diversity of his skill that earns him the high marks.
We could all easily name someone who was better than Shawn at technical wrestling, high flying, bumping, hardcore spots, mic skills (both heel and face), drawing money, longevity, psychology, etc. But someone who was really good at ALL of those things? That's rare.
That's why Shawn's great, in my opinion.