The Layout tabs of the control selector bar today are orderd as follows
Standard, Advanced, AUI, Contrib, Dialogs, KWIC, Layout, Led, MathPlot, Tool
Some of these classes are not maintained or even available any more. Some tabs far to the left contain classes that are used in almost every dialog, some futher to the right very rarely. I suggest the following reorder which puts the likely most often used controls to the left and the most rare used ones to the right.
My suggestion would be this
Standard, Layout, Advanced, AUI, Dialogs, Tool, Contrib, Led, MathPlot, KWIC