On the subject of graphics, you can attach a file in the notes field and view it in OmniFocus. If the picture is small enough, it will display inline (see screen shot below). If it is larger, you will need to use Quick Look.
For formatted text, try dragging the text into the notes field rather than copy/paste. Also in the screen shot below you can see part of the screen text that I dragged from your post into the note field. Even the links work when click on in OmniFocus. It does not retain 100% of the formatting, but it's pretty close.
