I guess (?) it shouldn't be too difficult to add a Markdown Tool which would allow to preview md files before to commit them. This would avoid the too many commits due to a missing blank line, etc.
The way I'm currently doing it is to go to the wiki, edit a dummy.md file, cut and paste from my local repo, switching from edit to preview and back. When I'm happy with, I cancel (of course) the changes on the web side, and I'm doing a regular commit. It works, but it is painful.
In brief: could you add a preview button when editing the README.md file?