tl;dr? Here's a Summary:
Here is a spreadsheet of the charge moves you can play with that uses an improved metric to rank charge moves. I've also included DPS*DPE and three new metrics (Damage/cycle with a cycle of 10s, 15s, and 20s) to show how they all stack up. Each column is formatted to list good moves in green and bad moves in red. The middle metric (with Frenzy Plant topping the charts at 344) is the metric I'd like to suggest using. Titled simply, it's the Damage/Cycle (10s):
Improvements by using this new metric:
You'll notice that moves like Precipice Blades and Origin Pulse do not outrank Frenzy Plant and Doom Desire. What's neat is seeing how moves like Dragon Claw, Draco Meteor, and Outrage stack up. With this new metric, Dragon Claw is still the worst of the three. But Draco Meteor actually out-ranks Outrage because you get to use more Quick Attacks during a cycle, generating some more damage and energy to make up for the loss in raw power.
But this still needs to be applied to the real world. Outrage has a significant advantage in being able to launch a powerful charge move for -50 energy. That means for 1.5 charge bars worth of energy, Outrage is out-damaging Draco Meteor. But for 2 charge bars worth of energy, Draco Meteor beats Outrage by ~20 points of damage. So to me, the moves are more equal than you'd think.
For the full analysis...