"More time" would equal "lower ROI" unless there is some magic inflection point that would cause a dramatic upward leap in gross margins. Gross margins, in this case, is mostly cost-per-user-acquisition. But "this new social network is amazing, I love it, and you should join" mostly happens when social networks are new, young, and small. It would be difficult to bring back the days of triple digit growth for a network the size of Reddit.