We already have that feature for threads that are created here on the forum. It includes share buttons for Google+, Twitter, and Facebook. Scroll down and look at the bottom of this page. I'm not sure if there is a feature that can be implemented to share individual posts from here to other sites.
If points system was to be added, i also agree that post / comment packages, etc.. shouldn't be added really. I would say having a "Forum Cash Exchange" forums would be good and people can earn points / forum cash by posting around then buying things directly from each other. So there would be a Forum Cash Exchange forum and the Community Collaboration forum for the non-forum exchange exchanges. Also could do things like restrict the number of links allowed in a signature, but this can be increased by purchased bigger sig allowance with forum cash. Things like that, but not posting packages, etc..
That said, i would use the post packages, etc.. if they where there, but in my opinion, you want to keep this forum as a place to learn about building and managing website, dont want to turn it into an exchange forum or package forum where that becomes the only reason people visit.