What other Lantern Corps would you like to see in DC Comics?

We know that in DC Comics, there are 9 Lantern Corps: Green (Willpower), Yellow (Fear), Red (Rage), Orange (Avarice), Blue (Hope), Indigo (Compassion), Violet (love), White (Life), and Black (Death). What other colors would you like to see in DC Comics, and what emotions would they correspond to? Personally, I would like to see a Grey Lantern Corps, representing ambivalence.