Launchpad Entry: https://blueprints.launchpad.net/inkscape/+spec/toolbar-resize
The purpose of this blueprint is to give a better organization to the toolbar of inkscape without effecting the space of the workarea itself.
[Write a brief one-line description of the feature we can paste into our ReleaseNotes when the feature's done.]
Adding new features to a program that should be used by a professional target user, needs also a good study of how the features are used too.
For example, I would expect that buttons that makes the same thing to happen, in this case the buttons that open a box with tool settings, are in the same area of the user interface and have a different look from the other buttons. This would give to the user an easier and more intuitive way to understand features, and to the new user to learn the software.
Also making the user interface more rationale and ordered, making easier to access and to find features and tools, gives to the le software a more professional look in general and improves the user experience.
[In this section, elaborate on the concept. Describe what the feature should do. Conceptualize how an artist's workflow would go. Identify UI changes needed, such as new buttons or dialogs. Include mockups or drawings if appropriate.]
First Step: Types of buttons
I would make these groups
 simple commands, like "cut", "copy", "open" etc.
 tools with options in a box, as the "trace bitmap" or most of the effects
 tools with options in the "tool controls bar", as "freehand lines" "rectangle" etc
 tools and commands that opens a setting box, as "layers" "stroke and fill" "path effects"
Second Step: Different position and shapes
Each group should have a position and a shape that identifies the type of action that it will do (referring to the groups above).
Group 4 should have icons near where the box will appear in the dock on the right, and in Group 3 should be underlined the link between the tool and the "tool controls bar".
Here's an example (a rough mockup)
* Flesh this specification out in more detail