My WF Archmage is now considering dropping Empower for Spell Penetration. (I could also drop Toughness for it, but I'd prefer to keep Toughness, I think. I like seeing nice high HP numbers, even if they aren't absolutely necessary.) No doubt, due to the stupid changes to Fred, this will require multiple feat swaps. But whatever. The Spell Penetration is desired for the Magister Piercing Spellcraft. Can someone give me a good reason NOT to drop Empower in the current endgame?