The current evolution of the site look has created a sidebar that is mostly empty space (screenshots from Super User):
It seems to me that it would be useful to transfer more information to the sidebar, in order to avoid the need for scrolling up in the page for the purpose of moving to another section of the display.
There is also a functionally strange point, that "Unanswered", which is really a sub-section of "Questions", is currently displayed twice, the second time in the sidebar on the same level as is "Questions".
Here is an example of what I think would be a functionally logical look for the sidebar:
