Personally, I don't really think this module requires documentation, as it is very straightforward, but I do intend on offering a quick-start guide for it soon. At this time my immediate plans for Simpl are to add functionality, continue to clean & lean the code, and get ready for Joomla! 3.5. If you have any questions about Simpl Extensions, feel free to hit me up on Twitter @coaleb.
Hope you enjoy using Simpl Extensions!