I agree with you. Markdown is meant to be very straightforward and simple, especially since it can be augmented with HTML. MultiMarkdown[1] and GFM[2] exist as variants of Markdown that can do much more, for those who want more... and I'm sure there are other flavors.

[1]http://fletcherpenney.net/multimarkdown/ [2]http://github.github.com/github-flavored-markdown/