If you like the semantic nature of these workspace layouts, maybe tiling window management is for you. Pretty much the same thing as screen in terms of how windows get arranged. Try [xmonad](http://xmonad.org) or [dwm/wmii](http://suckless.org) I find myself using only very few screen sessions because my WM takes care of most of the work, and only use it for persistent applications when I need to shut down X or launch irssi on a remote server, etc.