Seek your inputs for a Social Network Portal in Technical Communication

Folks,

I am in a process of designing a social network portal for technical communication and user experience design. I am planning to use Joomla as the open source tool for this purpose. To facilitate the process, I seek your assistance in two ways:

1) Please tell me what are the things that you feel that a social network portal in technical communication should consist of? I wish to make the portal interactive, so if you could tell me if blogs, quizzes, forums and so on can be of much help? Or, suggest me some ideas.

2) I need a web designer preferably someone who has worked in Joomla. I have the prototype ready and just want the designer' assistance in implementing the process. The designer will be paid a good remuneration. I can talk to the person about the remuneration part offline.

Appreciate if you can respond to me at holypriest at gmail dot com.

Thanks & Regards,
Rajdeep