Build site from scratch take time, And even you don't have to pay designer or web developer you will have to pay for the server(If you don't own one). I saw you mention about agreement on stealing idea. I think that if people saw very interesting idea they will probably steal it. There are hardly trust and royalty on the internet.
Yeah, i know it takes time, but that's not really a problem for me. A website from scratch is, in my opinion, much more powerful and useful than one from a template. There are cheap options for web hosting, but even in general it's not to expensive.
As for stealing data n other people's projects, it is up for the project poster to reveal how much information he wants to at the start. Hopefully, because of the community side of the site, people will be able to build pretty good friendships, and trust. Or at least choose who to trust and pm about their project. Also, the op would be the one with the team, so the stealer would have a hard time making an equal project. This in combination with the credibility ranking system, and the fact that there will be an elite ranking(like vip) to show that you have proven yourself trustworthy, i think that everything will be fine. We will also provide any other means neccesary to prevent stealing of information.(EZ doesn't even have these regulations, but I'm still working with Zesh.)
Thanks for your post though, you made some very good points, and a lot of criticism is always great. Actually, reading your post made me think of a few other ways to prevent idea theft