Those who wish to collaborate
I'm pleased to see the plan applying the Common European framework which allows materials to be matched up. Here course IV relates to A2 - which suggests that the basic user wordlist would be an appropriate goal http://www.wikieducator.org/ELT_Lexical_Syllabus/basic_user
I wanted to propose that the next step be the relatively small one between that and Simple English - the language of the Simple English wikipedia.
So far only one lesson done though: http://www.wikieducator.org/ELT_Lexical_Syllabus/simple_English/Categories