The left hand side tools menu already has a configurable enhancement so that one can have the icon on the left and the tool text next to it. This is controlled by the Sass variable $tool-menu-icon-on-left. This menu looks fine on a desktop sized screen.
On a mobile sized screen when the $tool-menu-icon-on-left is set to true the tools and subsites "buttons" should have a left-aligned image and be one to a line.
Also change the look of the buttons to be the same as those in the Sites tab