a) Have you first tried the Collapse, Expand options in the bottom right? Then yu can set those on the Customize to give the initial opening expand position.
b) After that you go to the Edit Layout and edit your existing layout. This is where you can move accounts between sections, display sections by department instead of GL.
c) You can also add entire new Financial Section if needed.
d) Adding a formula row is where yo might give the summary some additional calcs like an EBITA or a GP%