2 health for a card is hardly worth it. Why pay both health and mana crystals to draw 1 card? There's cards out there that will draw 3 cards for 3 mana crystals, and there's minions that have a battlecry that allows them to draw a card. There's so many ways to draw cards, and IMO spending both 2 mana crystals and 2 health is usually not worth it except in a few scenarios.
I feel like the other hero powers are better. Then again, I'm new.