All my suggestions start with questions;
Will the player have any spells he can direct even indirectly. - if so the button can be the Magic button.
Will the player be able to enter into diplomacy with neighboring cities and communities - if so the button can be the Diplo button.
Will there be an overarching tech tree of any kind - if there is this is a good place for it, and if not there could be a place that shows all classes and buildables available to help track and manage when that trapper is level three to switch them over to a shepard.
Love the roads.