Encouraging bilingual/trilingual/polyglots to contribute to new languages on Duolingo
It may encourage a wider net of people to contribute to the creation and testing of new languages on Duolingo if their efforts could be linked to their LinkedIn account (similar to how the fluency level of a language can be connected to someone's LinkedIn account)
Just a suggestion
My impression is that the (perceived) bottleneck in creating new courses is not a lack of volunteers. In fact, as I understand it, Duolingo already gets many more applications for volunteers than it can use and sorting through the numerous applications is a bit of a problem when the time comes to choose people to start work on a course.
Other resources (particularly staff time to supervise and assist, I imagine) are what is limiting the number of languages being worked on at any given time.
By the way, the reason I say "perceived" in my first sentence is that Duolingo always has a number of courses in progress and quite a number of them have gone through the entire creation and testing process and are now available.