So I've learned that because hybrid casters are out of control with their healing, if you're a DPS spec, you no longer benefit from the healing aspect of PVP Power. Unfortunately, Retribution's survivability consists almost entirely of active healing with Word of Glory and Flash of Light. Retribution Paladins are not completely out of control with their healing because they don't have nearly as much healing power as the hybrid casters do.
You can cast 2 Flash of Lights at a time, 3 if you wait for a couple more seconds. Even attempting to cast it once resets auto attacks and leaves you vulnerable to interrupts so it's sometimes risky as it should be, but I don't think it's overpowered, by any means. Word of Glory is used in lieu of Templar's Verdict and it's a necessary sacrifice sometimes but I don't think that is overpowered, either.
Maybe that's just me, though.