Quest-based learning is a fun, engaging, and innovative way to deliver a course but … Don’t do it all at once! If you are teaching a new class be careful to set realistic gaming goals. Start with something simpler like badges then gradually build to a quest-based approach. The badges used in one term can easily be rolled into quests if you plan for it.
Automatically assigned badges are more scalable than manual ones. Think about the value of developing learning objects that have built-in automation that can be used for awarding badges. Awarding badges based on activity completion is a good way to ensure scalability.
Adopting or adapting existing modular resources is a good place to start. Consider looking for modular open resources instead of creating your own content. Students are also good content-builders. Remember that you DO NOT need to do it all at once!