A different possibility is identifying vectors in Facebook-behavior space, and letting users alter their feeds accordingly, e.g. I might want to see my feed shifted in the direction of more intelligent users, people outside the US, other political views, etc. At the individual level, I might be able to request a shift in my feed in the direction of individual Facebook friends I respect (where they give general or specific permission).
A different possibility is identifying vectors in Facebook-behavior space, and letting users alter their feeds accordingly, e.g. I might want to see my feed shifted in the direction of more intelligent users, people outside the US, other political views, etc. At the individual level, I might be able to request a shift in my feed in the direction of individual Facebook friends I respect (where they give general or specific permission).