http://www.demon-heart.com/sims4/doris/Logo.jpg The Sims 4 Room Challenge is meant to test your management of social activities without the presence of other Sims. You build an 8 x 8 room on any ...
As far I've seen getting Pen Pals will only help you complete the Postcards collection, and won't fulfill any social need. Chatting and Trolling teh forums will.
If you have a mirror you can also raise your Charisma skill, which eventually gives you more social options on the computer, such as starting a social network.