OT about 10/GUI ( I can't visit that link currently, but I will soon ) but I have some ideas about deskbar, if you aren't interested skip please , the following text is written in a poor english too. Look at the attached mockup, please; it has been thought to manage windows with "layers" or "groups" like in image editors. Actually I don't mean to have something like this, but if the deskbar could manage custom groups beyond the current implementation by "application" the user can set as visible a group of windows at once with a simple click onto it, still using workspaces to take applications apart, if you haven't caught the concept with these messy words this is an example: (image not included)
dmw window manager and its fork, Awesome for X11 offer something similar: they have replaced conventional workspaces by "tags". Each window has one or more tags and the user can choose which tags are shown on his screen at a time. The user can build the desktop according to the task at hand. And because these are tabbing window managers, you don't need to reorganize the windows each time you change the tag set. I think this tagging stuff is a wonderful idea and use it on all my Linux setups.