MTG Salvation

I'm guessing that you intend to sideboard all the fatties when you bring in Dark Confidants. Otherwise, I wouldn't include Dark Confidant in the 75. It's pretty risky playing Dark Confidant without including ways to effectively manipulate the top card like: Brainstorm/Ponder/Jace, the Mind Sculptor/Sensei's Divining Top.

I think Firebolt is simply too expensive, and there isn't much that Lightning Bolt cannot already handle. I too would suggest Crippling Fatigue or Darkblast over Firebolt. I feel that the potential to Entomb for Crippling Fatigue/Darkblast may be more valuable than the extra two points of burn.