Fair enough :). For the record, Pandoc MarkDown supports all of these via its extended MarkDown syntax. For the first you can write [desc](src){.test} to get a class=test attribute on the link, for example. For the second, you can write {width=50%} to set the image size. For the last, tables do automatically get <th> on the first cell of each row when converted via Pandoc. This is however not standard MarkDown but Pandoc's extended version of MarkDown.