I do also agree on having one person in charge of that portion of the project which I'm trying to draft a team of talented developers and designers in order to delegate certain features off to the various people to best suit their skills and our needs... Mockups of how they think the site should look In my opinion is a part of setting up requirements....
You read my mind :)
We could even tie in OSQA - http://www.osqa.net/ - and get a Stack Overflow-like system. (That would really be a very suitable medium for Inkscape questions, I think. Better than the traditional forum model.) And the beauty of Django is that you can connect that to the rest - it doesn't need to be separate applications that you try to integrate, you dump the apps it uses into the project and it all Works. (Disclaimer: I haven't actually tried deploying OSQA yet.)
Like Alex said
> collecting requirements first and doing designs later.
Wiki page for the analysis?
Then, we can discuss if django-cms, our mashup of django apps or http://mezzanine.jupo.org/
(the new guy in the pack) as starting point.
Another thing, I don't know how the actual site was made, but in my opinion the new one should be "directed" by one and only one person or else everybody will ask for every functionality and opinions about shades of green will start to slow down the project. Sorry if it sounds harsh, english is not my first language.
A couple of phase can get us to our objective, not everything in one go. IMHO