I'm not sure if this is the place for feature requests, but I wanted to suggest two features for the Lesson module.
1.) I have found that I want all of my Lessons in a single course (or all of my courses, actually) to behave in the same fashion, and that it's a bit annoying to have to make sure that each Lesson has the same checks and YESs and Nos. I would rather go to one place that governs how all of the Lessons in that course operate. If you want to change one particular Lesson, then the settings in that individual Lesson could take precedence over the course level settings.
2.) Related to that, it seems like it would not be hard to create defaults for the Navigation. I've found that 95% of the time I want simple "Previous" and "Next" buttons for my Lesson pages (with just the "Next" on the first page). It seems like it would be nice to have a set of options in the Lesson settings for the text and relative pointers for those navigation buttons (So you could make yours all say "Retreat!" and "Onward!" if you want.) Then, when you're adding each page in turn, it would give you the same options as it does now, just with a checkbox that says "Use defaults" that you would uncheck before adding your own boxes, or adding other branches or whatever. Or it automatically knows that when you put text in those boxes, the defaults are not used...
Anyway, just my two cents. If there's another place for feature requests, I'll put this there, instead.