I've read Forever Evil and know that Earth-3 Hal was a coward, however how much of his characterization at that point was the influence of Volthoom was unclear. Inverted personalities of the other Earth Lanterns would have been great to see. John being unable to make a single decision, a meek Guy, heartless Kyle etc.
Given than Earth-3 Hal is dead obviously that's one less doppelganger. Would Jess have an Earth-3 counterpart? If so, she'd have the most insight into how to defeat her doppelganger since she'd also been a Power Ring.