See if there is a language that is further upstream than the rest, and also see if there is a language that is such a paradigm shift from the rest, and perhaps even from typical human-thought patterns, that many people from every group struggle to learn it. For those who don't, see if you can discover what is different about how they reason their way through programming.
Or perhaps find the language that everyone just gets once they've been exposed to one or more other languages. See if it really is the easiest, and more sparsely featured of the bunch, or if it just does a remarkably good job of unifying the concepts from all the others.
Just a couple of thoughts as I read your comment. :-)