The Treasury is a respected and influential central economic agency, and the Australian Government’s lead economic adviser.
Writing briefs, researching policy issues, doing some corporate contribution work, etc. Some tasks are, of course, more interesting than others.
I expected meaningful impact, but in practice the scope to influence outcomes is limited even higher up. With rotations, focus on units where you can apply and deepen skills you already have; that's where you'll get real development and value.