I'm a big fan of the all-singing all-dancing Design/Inflate - I find it gives much more 'realistic' terrains than I am capable of building myself...
I'm sure I'm not the only one who runs the Generate Design Map sequence over and over until I get the perfect looking result.
I'd love a keyboard shortcut for this task - I know it's not hard to trigger it through menus, but I'm kinda lazy like that...