Content aside, I love the idea of visualizing various skills and their relationships in this World of Warcraft - like style! Nicely done.

Khan Academy could be taking notes and inspiration to replace their current Knowledge Map:

https://www.khanacademy.org/exercisedashboard

Perhaps this would be a little over the top with gamification, but it could be cute to have a character sheet for every student with their level, experience points, skills and talent specs listed out in tabs. It's fun to look at Online Education as being essentially an MMORPG.