I do a considerable amount of work in the area of medical online decision-making tools—and have used most of the major quiz apps and learning management systems available. If anybody is considering building a quiz module for EE, I would suggest looking at survey software rather than quiz/e-learning apps for inspiration.
If you’re trying to do simple “right-wrong” answer quizes, you’ll probably be able to put something together in EE using variable input in short order. The limitation that most “quiz” and testing apps seem to have is that you cannot assign variable weights to different responses—then add branch or skip logic. An answer is generally “correct” or “incorrect.”
Survey apps, by contrast, are built from the ground up to assign weighted variable input—then track that input and branch according to it. At least the higher end survey apps, not the free online ones named after primates.
I wish you the best in building a quiz module: I can assure you that if you make it flexible and EE native, the market for it will be robust.