Just a mockup; feel free to edit and improve. 
Just thought us artists could have an option between wanting a thinner toolbox and broader one (depending on our screen size).
You could also try throwing in a colour wheel in here.
It is nice improvement. but should we group the tools a bit as the current version does?
In fact, I did have some ideas after read Blender UI Evolution pdf: we should remove all layers except the bline tool from toolbox, because they are not tools and add some real tools such as Link, Connect etc… into Toolbox It is just a dream, I know 