Maybe use the README file for the addon description, parse the manifest for game version compatibility and use the release description for the change log. You would need to convert the markdown to bbcode somehow, or allow markdown here on the site. Projects that do not have a manifest may need some other way to specify the compatibility and if the folder structure is not obvious it may be hard to find the manifest automatically, so it may be necessary to add some input field for the path.
Or add some fields that allow us to point to some text files like I made for
LibAddonMenu and read the necessary info from there.
On a side note, you probably should also update how the change log works and change it to a per file basis. Every uploaded file then automatically generates an entry with uploader, version and date and can have an optional description text. And please add a quick preview button to its input form.
