Word of warning, I am NOT a RDM (honestly find the job to be as dull as dirt) but I figure I'd throw out some randon idea that popped in my head to see if it would go anywhere.

Verholy - Reduces damage enemy deals by 5% for 10 seconds
Verflare - Increases magic vulnerability of enemy by 5% for 10 seconds

I'm aware this would make Verholy hardly ever used again since the whole "More Damage" mentality is pretty much always the way to go but I'm sure someone more knowledgeable than me could find a reason to justify Verholy and it's damage reduction use. If nothing else, it would give RDM more damage regardless.