I feel FE: Awakening's story would feel much different if I were playing on Classic. I haven't been able to keep Virion alive pretty much any time I've used him.
I understand why they removed perma-death from the game as an option, but considering the game is created and balanced around this core feature I think it lessens the experience very much to play without it.
If at all possible, you should restart the game and play on classic mode