I want to make it a go to place for people to establish and grow their identity as doers - to nurture their pursuits and benefit when they help others (If you are great at something you can mentor and invest/contribute open source in that field. The social capital you generate from doing that should come back to you as help in areas you are trying to grow in). Not everyone is comfortable putting that out there (especially non-hackers) and if they do, having real relationships with the other users on the site first helps. I would rather sacrifice short-term growth to build a product that really rocks and is spread by users in the mid-to-long term.
I'd be interested in understanding what pushed you in that direction. It would seem like it might slow down growth?