Second suggestions: The drawing board.
It's nice because when something we discuss there doesn't work, we say "back to the drawing board". And the chat is where we sketch ideas (that sometimes become meta essays or well-organized collaborations).
So we draw outlines on the drawing board and later discuss them in meta.
The quad is defined as:
a quadrangle, as on a college campus.
It is typically a central location where people go to hang out or and/or discuss important issues. Events are held on the quad, and it's generally a central multi-purpose area.